🔙 Quay lại trang tải sách pdf ebook Sách Giáo Khoa Hóa Học Lớp 10 Ebooks Nhóm Zalo ^ % -0 GIAO DUC VA DAO TAO I I •,':>ii'ir:'^'-- •::'^i-^^^ - '•".r/,. ; « .-.•.•.ff-.x' ^^ BO GIAO DUC VA DAO TAO NGUYfiN XUAN TRUONG (Tdng Chu bien kiem Chu bien) NGUYfeN DUC CHUY - LE MAU QUYEN - LE XUA N TRONG HOA HOC io (Tdi bdn ldn thd ndm) .'-<, 0 ^;'. tr. •i:f ",v,.. N H A XUA T BA N GIA O DUC VIET NAIVl Chiu trach nhiem xuai ban . Chu tich HDQT kiem Tong Giam doc NGO IRAN Al Pho Tdng Giam doc kiem Tong bien tap NGUYEN QUY THAO Bien tap lan dau : PHUNG PHLfONG LI^N - NGUYI N THANH GIANG Bien tap tai ban : HOANG KIEU TRANG Bien t$p mT thuat: NGUYI N HONG VY Thiet ke sach : PHAN Hl/ONG Minh hoa va trinh bay bia : PHAN HUONG SCra ban in HOANG KIEU TRANG Che ban : CONG TY CO PHAN Ml THUAT VA TRUYEN THONG Ban quyen thuoc Nha xuat ban Giao due Viet Nam - Bo Giao due va Dao tao Trong sach co sCf dung mpt sd hinh anh minh hoa lay ti/ sach nudc ngoai. HOA HOC 10 Ma so : CH007T1 In 100.000 cuon, (ST) kho 17 x 24cnn, In tai Cong ty TNHH mpt thanh vien In & Van hoa pham. So in: 176/11. SoXB : 01-2011/CXB/113-1235/GD. In xong va nop li/u chieu thang 1 nam 2011. Chuang MOmiM ^ Nguyen td cd ciu tao nhtr thi nao, tao nen tu nhiing hat gi ? Kich thudc, khdi lugng, dien tich cua chung ra sao ? • Hat nhan nguyen tu dugc tao nen td nhiing hat nao ? ^ cdu tao vo nguyen td nhu thi nao ? Mdi hen he giOa ciu tao nguyen td va tinh chit cua cac nguyen td. id phan Ung hat ntian tai Vien Nghien cCiu hat nhan, thdnh phd Bit Lat (tinh Lam Ddng) LL THANH PHAN NGUYEN TL/ • Bai • Nguyen tu co kfeh thuac, khoi lugng va thanh phan ca'u tao nhu the nao ? • Kich thuac, khoi lugng va dien ti'ch cua cac hat tao thanh nguyen tu la bao nhieu ? Hinh 1.1. Tugng De-mo-crit (Democritus) Hinh 1.2. Odng tien bang bae thdi De-mo-crit Vao khoang nam 440 trade Cong Nguyen, nha triet hoc De-m6-crit cho rhng dong tien bae bl chia nho mai, sau cung se dugc mot hat "khong thS phan chia dugc nita", goi la nguyen td (xuat phat tU chUHi Lap atomos, nghfa la "khong chia nho han dugc nCta"). Ngay nay, ngudi ta co the phan chia dugc cac nguyen tCt bae nhang cac hgp phan thu dugc khong con giO nguyen tinh chat cua bae nOa. Cho de'n tan giOa the' ki XIX, ngu6i ta vSn cho rang : Cac chat deu duoc tao nen tit nhiing hat cue ki nho be khong the phan chia duoc niia, goi la nguyen tu. Nhiing cong trinh thuc nghiem vao cuoi the' ki XIX, dau the ki XX da chung minh nguyen tir co that va co cau tao phiic tap. I - THANH PHAN CAU TAG CUA NGUYEN TL/ 1. Electron a) Su tim ra electron Nam 1897, nha bae hoc ngudi Anh Tom-xofn (J.J. Thomson) nghien ciiu su phong dien giiia hai dien cue co hieu dien the 15 kV, dat trong mot 6'ng gan nhu chan khong (ap sua't khoang 0,001 mmHg) va tha'y man huynh quang trong dng phat sang do nhiing tia phat ra tii cue am va duoe goi la tia am cue. Tia am cue eo cae dac tinh sau : - Tren duong di cua no, ne'u ta dat mot chong chong nhe thi chong chong bi quay. Dieu do cho thay tia am cue la chiim hat vat cha't CO khdi lugng va ehuyen dong vdi van tdc ldn. - Khi khdng cd tac dung ciia dien trudng va ttr trudng thi tia am cue truyen thang. - Khi cho tia am cue di vao giiia hai ban dien cue mang dien tich trai dau, tia am cue lech ve phia cue duong. Dieu dd chung to tia am cue la ehiim hat mang dien tich am (hinh 1.3). Tam kim loai tich dien lam thay doi ducfng di cua chum tia I5kv Man huynh quang Hinh 1.3. So cfo thi nghiem cua Tom-xan phat hien ra tia am cue NLIUOI ta iio\ nhuim hat tao ihaiiii lia am cue la cac election, ki hieu la e. b) Khoi lugng vd dien tich cua electron Bang thuc nghiem, ngudi ta da xae dinh dugc khdi lugng va dien tich ciia electron. Khdi lugng : m^ = 9,1094. IQ-^' kg. Dien tich : q^ ^ -1,602. lO^'^ C (culdng). Ngudi ta chua phat hien dugc dien tieh nao nhd hon 1,602.10"^^ C nen nd dugc diing lam ien iieli dun \ i, ki hieu la . Do dd, dien tieh ciia electron dugc ki hieu la - e^^ va quy udc bang 1 -. 2. Sir tim ra hat nhan nguyen tir Nam 1911, nha vat li ngudi Anh Ro-do-pho (E.Rutherford) va cac cdng su da eho cac hat a''* ban pha mdt la vang mdng va dung man huynh quang dat sau la vang de theo ddi dudng di eua hat a. Ket qua thi nghiem cho thay hdu het cac hat a deu xuyen thang qua la vang, nhung cd mdt sd it hat di lech hudng ban dau va mgt sd rat it hat bi bat lai phia sau khi gap la vang (hinh 1.4a, b). *' > Hat CO dien ti'ch 2+ va khoi lugng ga'p 4 ISn nguyen tir hidro. La vang mong Radi chira trong hop chi phdng ra tia a Man huynh quang Khe hd a) b) Hinh 1.4. Mo hinh thi nghiem kham pha ra hat nhcin nguyen td Nhu vay, ngu\en tir phai cinra plian mang dicn tluctiig cd khd'i lugng ldn de cd the lam eae hat a bi lech khi va cham. Nhung phdn mang dien tich duong nay lai phai cd kieh ihuoe rai nho so \oi kieh thuoe niiu\en tu de phan ldn cae hat a ed the xuyen qua khoang each giiia cac phan mang dien tieh duong ciia cac nguyen tii vang ma khdng bi lech hudng. Dieu dd chung td nguyen tu cd cau tao rong. phan mang dien dirong la hat nhan (hinh 1.4b). Xung quanh hat nhan ed eiie electron tao nen vo nguyen tu. De nguyen tir trung hoa ve dien, sd don vi dien tich duong eua hat nhan diing bang sd electron quay xung quanh hat nhan. Vl khd'i lugng cua cae electron rat nhd nen khdi luong ngu\ cn tii hau nhu tap trung a hat nhan. 3. Cau tao cua hat nhan nguyen tur a) Su tim ra proton Nam 1918, khi ban pha hat nhan nguyen tir nito bang hat a, Ro-do-pho da quan sat tha'y su xuat hien hat nhan nguyen tu oxi va mdt loai hat cd khdi lugng 1,6726.10~27 kg, mang mdt don vi dien tich duong (ki hieu la e^ ; quy udc bang 1+). Dd ehinh la hat proton, duge ki hieu bang chii p. Hal prolon la moi ihaiili phan eau tao eua hat nhiin nguyen tu. b) Su tim ra natron Nam 1932, Chat-uych (J.Chadwick) (edng tae vien cua Ro-do-pho) dung hat a ban pha hat nhan nguyen tir beri da quan sat thay su xuat hien ciia mgt loai hat mdi ed khdi lugng xap xi khd'i lugng eiia proton, nhung khdng mang dien, duge ggi la hat notron (ki hieu bang chii n). Nhu vay, nolron eiing lii mot thanh phan eiiu tao eua hai nhan nguyen tu. c) Cdu tqo cua hqt nhdn nguyen tu Sau cae thi nghiem tren, ngudi ta di den ket luan : Hat nhan ngu\en tu dirge lao thimh bai eiie prolon vii ncrtron. VI niTlron khong mang die-n, sd proton irong hai nhiin phai bimg sd di^i vi dien tieh diKTiig eiia hat nhan vii bimg sd electron qua\ xung quanh hiil nhan. II - KICH THUOC VA KHOI LUONG CUA NGUYEN TU Ngay nay, cac nha khoa hge da xac dinh duge kieh thude va khdi lugng cac hat tao nen nguyen tir. Nguyen tti ciia cae nguyen td khae nhau cd kich thudc va khd'i lugng khae nhau. 1. Kich thudfc Ne'u hinh dung nguyen tir nhu mdt qua eau, trong dd cd cac electron chuyen ddng rat nhanh xung quanh hat nhan, thi nd cd dudng kinh khoang 10~'° m. De bieu thj kieh thudc nguyen tti, ngudi ta dung don vi nanomet (viet tat la nm) o hay angstrom (viet tat la A). Inm = 10" m ; 1 A = 10' " m ; 1 nm - 10 A. a) Nguyen tu nhd nha't la nguyen tir hidro cd ban kinh khoang 0,053 nm. b) Dudng kinh ciia hat nhan nguyen tu cdn nhd hon, vao khoang 10"^ nm. Nhu vay, dudng kinh cua nguyen tu ldn hon dudng kinh ciia hat nhan 10-'nm khoang lOOOOMn 10-5nm = 10^ Neu ta hinh dung hat nhan la qua eSu cd dudng kinh 10 cm thi nguyen tir la qua cau cd dudng kinh 1000 m = 1 km. e) Dudng kinh cua electron va eua proton cdn nhd hon nhieu (khoang 10"^ nm), electron chuyen ddng xung quanh hat nhan trong khdng gian rdng cua nguyen tu. 2. Khoi lirong Ta khd tudng tugng dugc rang 1 g cua bat ki chat nao eung ehiia tdi hang ti ti nguyen tii. Thi du : \ g cacbon cd tdi 5.10^^ (50 OOO.IO'^.IO'^) nguyen tir cacbon (tiic la nam muoi nghin ti ti nguyen tir cacbon). Vi vay, de bieu thi khdi lugng cua nguyen tir, phan tir va eae hat proton, notron, electron ngudi ta phai dung inn w klioi lirong ngLi\en ur. ki hieu la *'*, u edn dugc ggi la dvC. I 1 Ll bane - khoi IUOIILL eua moi nuu\en ur done \ i eaebon-12. . | , . . .. . Nguyen tir cacbon nay cd khdi lugng la 19,9265.10"^^ kg. ^^J9,9265.10-^^kg^ 3^^,, , 12 Khdi lugng cua 1 nguyen tir hidro la l,6738.10-2'7 kg = l,008u = lu. Khdi lugng ciia 1 nguyen tir cacbon la 19,9265.10"^^ kg - 12u. Khdi lugng, dien tieh eiia eae hat eau tao nen nguyen tir dugc ghi trong bang 1. Bang 1. Khdi lugng va dien tich cua cac tiat tao nen nguyen tu Oac tinh hat Vo nguyen tu electron (e) proton (p) Hat nhar 1 notron (n) Dien tich q Khoi luclng m qj=-1,602.10-13 C =-e„=1- mg= 9,1094.10-3'kg mg=0,00055u qp=1,602.10-'8c = e„=1+ mp= 1,6726.10-2'kg mp=1u qn=o m„= 1,6748.10-2'kg m„ = 1u (1) Trong mdt sd tai li6u nuoic ngoai, ngucri ta con gpi la amu (atomic mass unit). 8 BAI TAP 1. Cac hat ca'u tao nen hat nhan cua hau he't cac nguyen tCr la A. electron va proton. B. proton va natron. C. natron va electron. D. electron, proton va natron. Chpn dap an diing. 2. Cac hat ca'u tao nen hau het cac nguyen tCr la A. proton va electron. B. notron va electron. C. notron va proton. D. natron, proton va electron. Chpn dap an dung. 3. Nguyen tCr c6 dudng kinh I6n gap khoang 10 000 lan dudng kinh hat nhan. Neu ta phdng dai hat nhan len thanh mpt qua bong cd dudng kfnh 6 cm thi dudng kinh nguyen tCr se la A.200 m. B.300 m. C. 600 m. D.1200 m. Chpn dap sd dung. 4. Tim tl sd ve khdi lupng cua electron so vdi proton, so vdi notron. 5. Nguyen tCr kem cd ban kinh r = 1,35.10"^ nm va cd khdi lupng nguyen tCr la 65 u. a) Tinh khd'i lupng rieng cCia nguyen tCr kem. b) ThUc te hau nhu toan bp khdi lupng nguyen tCr tap trung 6 hat nhan vdi ban kinh r = 2.10"^ nm. Tinh khdi lupng rieng cua hat nhan nguyen tCr kem. Cho biet V,.„,^, = |'rr3 . L l B^i HAT NHAN NGUYEN TU NGUYEN TO HOA HOC DONG VI • Su lien quan giua so don vi dien tich hat nhan vai so proton va so electron. • Sd khoi cua hat nhan duac tfnh nhu the nao ? • The nao la nguyen to hoa hoc, d6ng vi, nguyen tii khdi, nguyen tii khoi trung binh ? I - HAT NHAN NGUYEN TU 1. Dien tich hat nhan a) Proton mang dien tich 1 +, neu hat nhan cd Z proton thi dien tieh ciia hat nhan bang Z+ va sd don vi dien tich hat nhan bang Z. b) Nguyen tu trung hoa ve diSn nen sd proton trong hat nhan bang so electron ciia nguyen tu. Vay trong nguyen tir: So don \ i dien tfeh hat nhan Z = sd prolon = so electron Thi du : Sd don vi dien tich hat nhan eua nguyen tu nito la 7, vay nguyen tir nito ed 7 proton va 7 electron. 2. So khoi a) Sd khdi (ki hieu la A) la tdng sd hat proton (ki hieu la Z) va tdng sd hat notron (ki hieu la N) eiia hat nhan dd : A = Z + N Thi du, hat nhan nguyen tir liti cd 3 proton va 4 notron, vay sd khd'i ciia hat nhan nguyen tir liti : A = 3 + 4 = 7 b) Sd don vi dien tich hat nhan Z va sd khdi A dae trung cho hat nhan va ciing dac tnmg cho nguyen tir, vi khi biet Z va A eiia mgt nguyen tir se biet dugc sd proton, sd electron va ca sd notron trong nguyen tir dd (N = A - Z). Thi du : Nguyen tir Na cd A = 23 va Z = 11, suy ra nguyen tir Na ed 11 proton, 11 electron va 12 ncrtron. M M . . 10 II - NGUYEN TO HOA HOC 1. Djnh nghla Tinh chat hoa hge cua nguyen td phu thude vao sd electron eua nguyen tir nguyen td dd va do dd phu thuge vao sd don vi dien tieh hat nhan Z eiia nguyen tir. Nhu vay, cac nguyen tir cd eiing sd don vi dien tich hat nhan Z thi ed cung tinh chat hoa hgc. Dinh nghTa : Nguyen td hoii hge lii nhiing nguyen ui' ed eimg dien li'eli hat nhiin. Thi du : Ta't ea cac nguyen tir cd eung sd don vi dien tich hat nhan la 11 deu thude nguyen td natri. Chiing deu ed 11 proton va 11 electron. Cho den nay, ngudi ta da biet 92 nguyen td hoa hge cd trong tu nhien va khoang 18 nguyen td nhan tao dugc tdng hgp trong cae phdng thi nghiem hat nhan (tdng sd khoang 110 nguyen td'). 2. So hieu nguyen tur Sd don vi dien tfeh hat nhiin nguyen tu eua mgt ngu\en id duge ggi lii sd hitHi nguyen tu eua nguyen to dd. kf hieu lii Z. 3. Ki hieu nguyen tu So don \ i dien tfeh hai nhan va so khoi dugc coi la nhiing dac trung eo ban ciia nguyen tir. De' ki hieu nguyen tir, ngudi ta thudng dat ki hieu cac chi sd dac trung d ben trai ki hieu nguyen td X vdi sd khdi A d phia tren, sd hieu nguyen tir Z d phia dudi: ^ X. Thi du : S6 kh6i A Ki hieu hoa hoc So hieu nguyen tCrZ Ki hieu tren cho ta biet: So hieu nguyen tir cua nguyen td Na la 11 nen sd don vi dien tieh hat nhan nguyen tir la 11, trong hat nhan ed 11 proton va vd nguyen tir Na cd 11 electron. So khdi eua nguyen tir Na la 23 nen trong hat nhan ed 12 (23-11=12) notron. 11 Ill - OONG V| Cac nguyen tir ciia ciing mgt nguyen td hoa hgc ed the ed sd khdi khae nhau vi hat nhan ciia cac nguyen tir dd cd sd proton nhu nhau nhung cd the cd sd notron khae nhau. ( ae doii'.: \ i eua Liiiig nuM n>_:u>eii lo hoii IKK la nhung ngii\en ui eo eung so PI-' " • 'r ' '• •• i '• 1 I • -.n iidiron, tin do s('i klioi \ eu,i JmiiL' khae nhau. Cac ddng vj dugc xep vao ciing mdt vi tri (6 nguyen td") trong bang tuan hoan. Thi du. nguyen td hidro cd ba ddng vi : a)Proti(]H) Hat nhan gom 1 proton (tn/dng hap duy nhai fihong CO notron), chiem 99,984% s6 nguyen tii hidro ta nhien. b)Dateri(;H) Hat nhan gom 1 proton va 1 notron, chiem 0,016% so nguyen hi hidro tiT nhien. c)Triti(^H) Hat nhan gom 1 proton va 2 notron (trudng hap duy nhat co so natron b^ng 2 lan so proton). Borig vi nay chi chiem l nc)i tang con ngucTi, ve hoat dono c ua c ac c o c|uaii iic^r,o bict, plmc vu c ho (han doan b()nh, Tia phong xa diKrc su dung trong c ac phucni.; pliap c hup c ai lop, Tu lau ngirc'n ta da su dung d(")ng v| ' " 1 trong ( han doan v ,i dii^u ti i licnh luv cMI i;iap TM CO the' hen tu lao ihanh c hum tia co nang lucnv.^ Icni cluoc sn clune nhu mot knn dao s,i( (dao gamma> trong c ac ( a mcj khong c hav nu u doi \ (n c ,ic khoi u n.im s,ui in mo n,"ii > ma benh nhan killing c i^^ |)liai gay me v a c o ilic di l.ii duoc ngav sau c a mo,,, N,im 2oi i"i, mc')t I hiet bl "d.io L;amm,i" nhu v ay (l:t diroc du,i v ao su clung cr \'i(-l N.im (t.ii bcnli \ HMI Trirong t)ai hoc Y khoa Huel, c) IJnfi dun<^ cl('>ng vl phong \a trong cong nghiep va nghien ctru khoa hoc Pliiicrn;^ phap nguyen tu danli diiu ducri dimg rimg rai de theo doi su di (huyen c lia nirc'rc mat, nuirc ngiim, kiem tra toe do Iham t|ua dt', dap, tham do dau khf, nghien ciru ecr che cua ( a( phan ung phuc lap va do t\M e ac hang so hoa If. Tia y (ven kha niing diim xuyen manhl c ho phep kiem tra do diie khil e ua bt' long va cac vilt lieu ket khen, phat hien e .le khuyet tai nirt, gay nam sau trong viit lieu mil khong phai pha mini, Nang lircrng e ua tia phong xa co the gay ra nhieu bien din hoa hoe, bit'n tinli nhk^u viit lieu tao III eae vai lieu men vcri nhirng linh c hiit cue ki dejc dao, Cae phucmg phap hat nhim e cj kha niing phat hien tap chat o niini; di) rat nho (!()"" - It) ''), da lam thay de")i dang kt- dien mao cua Hoa hoc phim lich hien dai, f'him lie h dcjiyo vi cho phep xae dinh lucii ciia man dat da hoac mim hoa thach... 3. Sudun g niing luejng phan hach Su phan hach giai phong inot nang lirerng khimg lei, Tir phuang trinh (1), ngucri ta tinh ra rang nang lircrng phan hach eua I kg -''U , cei iht' lich ecr meil qua bong ten-nit, tircmg direrng veVi nang lirong thu duac khi ddt chay 2000 tiin than (so than niiy phai chuyi'ii ( her hang 200 chuyen xe tai 10 tan), hoac niing luang ciia su no 20 000 tiin thuoc no TNT, Niing luang phiin hac h eua iirani direrc sir dung trong cac nhii may dien hat nh.in. Nam 2005, nang lucmg nay dii cung cap khoang \b"/n teing san lircTng dien ciia the glcxi, Dit-n hat nhan hiiu nhu khong phat thai khi CO , vii cac khi thai (UK hai khae, chi phf nhien lieu thap, ec^ the la mot lira c hon hap If cho sir phat tnen ben virng cua nirac la va nhii'u i|uoe i;ia khae. 4. Bao ve phong xa Tia phong xa cei tlie anh hircjng nghiem trong dc>n sue khoe con ngiroi va dong, thuc vat, Khi l.im vitj^c voi r,M dcmg vi |.)lic)ng xa, phai tern Iremi; tnet de c ac e|u\ dmh ve ^n lo.in hat nhan, ( ae c hat thai phong xa ph.ii duoe xu ll theo cac (|uv lrinh nghii'iii ngat va e he')n chat thai Iron'. e\ic klio duoe xay dirng dae bii't, \)n\ ven e liiil 111,11 hoat dci caej, c ae klio ill,a pliai ,111 lo.in trong thcri gian hang v,)n nam. 16 Phong dong vi phong xa, Vien Nghien cUu hat nhan, thanh pho Da Lat (tinh Lam Dong). • Bai Li B«i LUY^N TA P : THAN H PHAN NGUYEN TLJ • Cung cd kie'n thuc ve : - Thanh phan cau tao nguyen tu, hat nhan nguyen tu, kich thuac, khdi luong, dien tfch cua cac hat. - Oinh nghTa nguyen td hoa hoc ; Kf hieu nguyen tu, d6ng vi, nguyen tu khdi, nguyen tu khdi trung binh. • Ren luyen kf nang xac dinh sd electron, sd proton, sd notron va nguyen tu khdi khi bie't kf hieu nguyen tu. A - KI^N THUC CAN NAM VQNG 1. Nguyen tii duoc tao nen boi electron \a hat nhan. Hat nhan duoc tao nen bm proton va notron q^ = -1,602.10-^9 C, quy udc bang 1- ; m^ « 0,00055u. q = 1,602.10-'^ C, quy udc bang l-t-; m « lu. q„ = 0;m„«lu . 2. Trong ngu>en tu, so doti \| dien tich hat nhan Z = sd proton = so electron Sd khd'i A = Z + N. Nguydn tu khd'i coi nhu bang tdng sd cac proton va cac ncrtron (g& diing). Nguy6n tiJ khdi ciia mdt nguyen td cd nhieu ddng vj la nguyen tur khd'i trung binh ctia cac ddng vj dd. NguySn td hoa hoc la nhung nguyen tir cd ciing sd Z. Cac ddng vj ciia mot nguyen td hoa hoc la cac nguyen tti cd ciing sd Z, khae sd N. 3. So hieu nguven tu Z va so khoi A dac trung cho nguyen tii Kl hieu nguySn tir: ^X. 2-HH10-C/A 1 7 B-BAITAP 1. Theo sd lieu 6 bang 1 bai 1, trang 8 : a) Hay tfnh khdi luong (g) cua nguyen tur nito (gom 7 proton, 7 notron, 7 electron). (Day la phep tfnh gan dung.) b) Tfnh tl sd khdi luong cua electron trong nguyen tCr nito so vdi khdi lUdng cua toan nguyen tCr. 2. Ti'nh nguyen tCf khdi trung binh cua nguyen td kali, bie't rang trong tu nhien thanh phan phan tram cac dong vi cua kali la : 93,258% ^^K ; 0,012% {°K va 6,730% ^''^K. 3. a) Dinh nghTa nguyen td hoa hoc. b) Ki hieu nguyen tCr cho bie't nhumg dac trUng gi cua nguyen tir, lay thf du vdi nguyen tCr kali. 4. can CLf vao dau ma ngudi ta bie't chac chan rang giura nguyen td hidro (Z = 1) va nguyen td urani (Z = 92) chi cd 90 nguyen to. 5. Tfnh ban kfnh gan diing ciia nguyen ti!f canxi, bie't the tfch cue 1 moi canxi tinh the bang 25,87 cm^. (Cho bie't : Trong tinh the, cac nguyen tCf canxi chi chiem 74% the tfch, cdn lai la khe trdng). 6. Viet cong thdc ciia cac loai phan tCf d6ng(ll) oxit, bie't rang ddng va oxi cd cac ddng vi sau : 65p, , 63p. . . 16(-) 17f-) 18/-) 29'"" ' 29*"" ' 8^' 8^ ' a'-'- 1 8 2-HH10-C/B f Bai Li CAU TAO VO NGUYEN TU • Trong nguyen tu, electron chuyen dpng nhu the nao ? • Ca'u tao vo nguyen tti ra sao ? The nao la lop, phan lop electron ? Mdi lop, mdi phan lop co tdi da bao nhieu electron ? I - s y CHUYEN DON G CUA CAC ELECTRON TRONG NGUYEN TU Nhiing nam dSu cua the ki XX, ngudi ta cho rang cac electron chuyen ddng xung quanh hat nhan nguyen tir theo nhiing quy dao trdn hay bSu due, nhu quy dao ciia cac hanh tinh quay xung quanh Mat Trdi. Dd la md hinh miu hanh tinh nguyen tir cia Ro-do-pho, Bo (N.Bohr) va Zom-mo-phen (A.Sommerfeld). Md hinh nay cd tac dung rat ldn de'n sU phat trien If thuyet ca'u tao nguyen tu, nhung khdng day dii de giai thfch moi tfnh cha't ciia nguyen tiJr. Ngay nay, ngudi ta da bie't cac electron cliuycn dong rai nhanh (td'c do hang nghin km/s) Irong khu virc xung qiianli hai nhan Electron_ Hat nhan Quy 6ao electron Hinh 1.6. Mo hinh mau hanh tinh nguyen tCr cCia Ro-do-pho, Bo va Zom-ma-phen 111 ngiivcn 111 klioii'j ihi.-o nlu7n<_! c|ii\ dao vac_ dinh'' ' lao nen vo nenven lu. Sd electron d vd nguyen tir ciia mot nguyen td diing bang sd proton trong hat nhan nguyen tu va cung bang so hieu nguyen tir (Z) hay sd thti tu cua nguyen td dd trong bang tuan hoan. Chang han, vd ctia nguyen tii hidro (Z = 1) cd 1 electron, vd ctia nguyen tu clo (Z = 17) cd 17 electron, vd ciia nguyen tii vang (Z = 79) cd tdi 79 electron,... Vay cac electron dugc phan bd nhu the nao ? Cac ket qua nghien ciiu cho thay chiing phai phan bd theo nhiing quy luat nha't dinh. "* Xem khai niem obitan nguyfin tir (Bai doc them "Khai niem vg obitan nguyen tir", trang 22). 19 II - L6P ELECTRON VA PHAN L6P ELECTRON 1. Lop electron Cac electron trong nguyen tir d trang thai ca ban Mn lugt chie'm cac miic nang luong tir thap de'n cao va sap xe'p thanh timg ldp. Cac electron d gSn nhan hon lien ket bdn chat hon vdi hat nhan. Vi vay, electron d ldp trong cd miic nang lugng thap hon so vdi d cac ldp ngoai. < ':ii, eie iri'i i '••.••\ enne ini>' h'p co niiiL naivj hrcrn:.' L'an haive nlian Xep theo thii tu miic nang lugng tir tha'p de'n cao, cac ldp electron nay dugc ghi bang cac sd nguyen theo thii tu n = 1, 2, 3, 4 ... vdi ten ggi: K, L, M, N, ... n = i : .^1 4 len lop K L M N 2. Phan Idp electron Mdi ldp electron lai chia thanh cac phan ldp. Cae eleeiron IILI I cune inoi |IIKII I iO|i eo nine ii.ing lii'oivj bang nhan ( 'ai_ phan lop duoe ! hit eai ihn'o'ng s. p. d. I. Sd phan ldp trong mdi ldp bang sd thii tu ciia ldp dd. Ldp thli nha't (ldp K, n = 1) cd mdt phan ldp, dd la phan ldp Is ; Ldp thli hai (ldp L, n = 2) cd hai phan ldp, dd la cac phan ldp 2s va 2p ; Ldp thli ba (ldp M, n = 3) cd ba phan ldp, dd la cac phan ldp 3s, 3p va 3d ; v.v... Cac electron d phan ldp s dugc ggi la cac eiron d phan ldp p dugc ggi la CaCeU . i,..i, j . ... Ill - S6 ELECTRON T6 | OA TRONG MO T PHAN L6P, MO T LOP Sd electron tdi da trong mdt phan ldp nhu sau : re.:.. .• i . ei,.: ; -i e, ._ .:. .ii>.:; . I'll.Ill il ip pi. Ilea loi cl.i U liec iron . I 'h.iii lop I i 1 liiia lc a ila III I'lei. Unn ; Phan ldp electron da cd dii SO electron tdi da ggi la em lopeleui.m h.io hoa, Tir dd suy ra sd electron td'i da trong mdt ldp : 1. Ldp thli nha't (kvp K, n = 1) cd 1 phan ldp Is, chtia td'i da 2 electron. 2. Ldp thli hai (ldp L, n = 2) cd 2 phan ldp 2s va 2p : - Phan ldp 2s chiia tdi da 2 electron ; - Phan ldp 2p chiia td'i da 6 electron ; Vay, ldp thli hai chiia td'i da 8 electron. 20 3. Ldp thli ba (ldp M, n = 3) cd 3 phan ldp 3s, 3p va 3d : - Phan ldp 3s chiia td'i da 2 electron ; - Phan ldp 3p chiia td'i da 6 electron ; - Phan ldp 3d chiia tdi da 10 electron ; vay, ldp thli ba chiia tdi da 18 electron. Tii cac thf du tren nit ra rang : ^''' electron icn da eua lop ihii n ' ^•--. Dua vao cdng thiic nay tfnh dugc ldp thii tu (ldp N, n = 4) chtia td'i da 2.42 = 32 electron. Ldp electron da cd dii so electron td'i da ggi la lop eleeiron bao hoa. Bang 2. So electron tdi da trong cac lap va cac plian ldp (n = 1 den 3) , j,_ . . So electron Phan bo electron i-op electron toi da 1 cua ldp tren cac phan ldp L6pK(n = 1) Ldp L (n = 2) L6p M (n = 3) 2 8 18 1s2 2s22p6 3s23p63dio Thi du : Xac dinh so ldp electron ciia cac nguyen tir '^N, ^2^§- So don vi dien tfch hat nhan ctia nguyen tu nito la 7, suy ra hat nhan cd 7 proton, vd nguyen tii cd 7 electron dugc phan bd nhu sau : 2 electron tren ldp K (n = 1), 5 electron tren ldp L (n = 2). Cung lap luan nhu tren vdi nguyen tir magie, hat nhan cd 12 proton, vd nguyen tu cd 12 electron dugc phan bd nhu sau : 2 electron tren ldp K (n = 1), 8 electron tren ldp L (n = 2) va 2 electron tren ldp M (n = 3) (xem hinh 1.7). 1*N Hinh 1.7. So dd suphan bd'electron tren cac ldp cda nguyen tdnita va magie (Vong tron trong cung tUdng trung cho hat nhan c6 chiia notron (n) va proton (p), cac vong tron ngoai tupng trUng cho cac ldp electron) 21 BAI TAP 1. Mot nguyen tur M co 75 electron va 110 notron. Kf hieu cCia nguyen tCr M la A.f^M. B.^llM. C.^;°M. D.^^^M. Chpn dap an diing. 2. Nguyen tii nao trong cac nguyen tuf sau day chda ddng thdi 20 notron, 19 proton va 19 electron ? A. 3^CI. B. 39K. C.;°Ar. D. ;°K. Chon dap an diing. 3. So don vi dien tfch hat nhan ciia nguyen tCr flo la 9. Trong nguyen tii flo, sd electron 6 phan mdc nang lugng cao nha't la A. 2. 8.5. C. 9. D. 11. Chon dap sd diing. 4. Cac electron cua nguyen td nguyen to X dugc phan bd tren 3 Idp, Idp thii ba c6 6 electron. Sd dOn vj dien tfch hat nhan nguyen td cua nguyen td X la A. 6. 6.8. C. 14. D.16. Chpn dap sd diing. 5. a) The nao la Idp va phan Idp electron ? Su khae nhau giura Idp va phan Idp electron ? b) Tai sao Idp N chiia tdi da 32 electron ? 6. Nguyen tdagon co kf hieu la ^"Ar. a) Hay xac djnh sd proton, sd natron va sd electron cua nguyen tii. b) Hay xac dinh su phan bd electron tren cac Idp electron. Bdi doc them KHAI NIEM VE OBITAN N(JL YEN TLf Mot electron trong nguyen tii hidro chuyen dpng cue nhanh trong khu vuc khong gian gan hat nhan nguyen tii tao thanh mpt dam may electron (hinh 1.8). Mat dp dien tfch cua dam may electron do lan nha't a ben trong mpt hinh cau c6 ban kfnh 0,053 nm. O khu vuc do, kha nang co mat electron la khoang 90%. Ta noi do la obitan Is. 22 ^; m: Hinh 1.8. Dam may electron hinh cau cua nguyen til hidro Nhu vay : ' >l'itan ni^uvcn in ia klui VLH klic')ni; ^lan \niii; c|naiiii iial nhan lai f1c) \ac "-u.il c I) 111,11 lieiv \,i( '^lMl lull lliav ' fic^c liciii i,i klioaiii; 'ii)",,_ Obitan nguyen tu duac viet tat la AO (Atomic Orbital). O phan lop s co 1 obitan s. O phan lap p co 3 obitan p^, p , p^ vuong goc vai nhau trong khong gian nam tren true x, y, z ciia he toa dp D^ cac. Cac obitan p co dang hinh so 8 noi (hinh 1.9). .A AOs AOp, A0p„ AOp, Hinh 1.9. Htnh dang cua cac obitan s va p d phan lap d co 5 obitan d, hinh dang phuc tap hon. Moi cihil.in c iina loi cki _! eicc lion \'\c'\) : I'iian lop SCO 1 oliitan ^ c luia loi cki 2 eleeiron, I'lian Ici-p p (Cl i cihiijn |i c lura ten ria d electron, I'll,In lcr|i fl CII 'i c iliiljn fl c luia ten da I 0 dec in in, Khai niem obitan nguyen tu giup ta hieu cac khai niem khae nhu : su lai hoa cac obitan, lien ket o (xfch ma), lien ket n (pi) se dupc hpe sau nay. 9m • Bai Li CAU HINH ELECTRON NGUYEN TU • Su sap xep cac electron trong vo nguyen tu cac nguyen to nhu the nao ? • Ca'u hinh electron ciia nguyen tii la gi ? Cach vie't cau hinh electron ciia nguyen tii. • Dac diem ciia lap electron ngoai cung. I - THLT TLT CAC MUC NAN G LL/ONG TRONG NGUYEN TL/ Cac electron trong nguyen tu d trang thai CO ban lan lugt chiem cac miic nang lugng tir thap de'n cao. Tir trong ra ngoai, miic nang lugng ciia cac ldp tang theo thii tu tii 1 de'n 7 va nang lugng cua phan ldp tang theo thii tu s, p, d, f. Sau day la thir tu sSp xe'p cac phan ldp theo chidu tang cua nang lugng dugc xac dinh bang thuc nghiem va If thuye't: K ^s ^1 ^^s M. -K 3d 4n Ss (hinh 1.10). 4f 3d ip is 2p ^s 1 's MCrc nang luong Phan mirc nang li/ong Hinh 1.10. Sa dd phan bd mUc nang lUOng cua cac ldp va cac phan ldp Khi dien tfch hat nhan tang, cd sir chen miic nang lugng nen miic nang lugng 4s tha'p hon 3d. II - CAU HINH ELECTRON NGUYEN TU 1. Cau hinh electron nguyen tir C an hinh eleeiron nguven tu ineti ilieii sir phan lio eleeiron tren e.ic ph.m lop llitioe ca^ lo|i khae nhau, Ngudi tai-|ii\ uoe taeh v lei L,IU iiinli eleelion nguven lu nhU sau : - So thli tu ldp electron dugc ghi bang chii sd (1, 2, 3...). - Phan ldp dugc ghi bang cac chii cai thudng (s, p, d, f). - So electron trong mgt phan ldp dugc ghi bang so d phfa tren ben phai cua phan ldp (s-, p^,...). 24 (Vieh viel eau Innli eleeiron nguvcMi Ur gom e.ie biroe sau : Bui re I Xac dinh sd electron ciia nguyen tii. Biroe 2 Cac electron dugc phan bd 1^ lugt vao cac phan ldp theo chieu tang ciia nang lugng trong nguyen tii (Is 2s 2p 3s 3p 4s 3d 4p 5s... ) va tuan theo quy tac sau : phan ldp s chiia td'i da 2 electron ; phan ldp p chtia td'i da 6 electron ; phan ldp d chiia tdi da 10 electron ; phan ldp f chiia tdi da 14 electron. Biroe e Vidt ca'u hinh electron bieu di6n su phan bd electron tren cac phan ldp thudc cac ldp khae nhau (Is 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s ...). Thi du : - Nguyen tu hidro, Z = 1, cd 1 electron. Cau hinh electron ciia nguyen tu H la Is'. - Nguyen tir heli, Z = 2, cd 2 electron. Cau hinh electron cua nguyen tu He la 1 s^, da bao hoa. - Nguyen tti liti, Z = 3, cd 3 electron. Cau hinh electron ciia nguyen tu Li la ls^2s'. Electron cud'i ciing cua nguyen tu liti di6n vao phan ldp s. Liti la nguyen td s. - Nguyen tir clo, Z = 17, cd 17 electron. Cau hinh electron ciia nguyen tu Cl dugc vie't nhu sau : Is22s22p^3s^3p^. Hoac viet ggn la : [Ne] 3s^3p^. Electron cud'i cdng ciia nguyen tii clo dien vao phan ldp p. Clo la nguyen td p. [Ne] la kf hieu ca'u hinh electron ciia nguyen ttr neon, la khf hie'm gan nhat dirng trudc clo. - Nguyen tu sat, Z = 26, cd 26 electron. Cac electron ciia nguyen tii Fe dugc phan bd nhu sau : Is22s22p^3s23p^4s23d6. Electron cud'i ciing ciia nguyen tii Fe di6n vao phan ldp d. Sat la nguyen td d. ca'u hinh electron cua nguyen tu Fe : ls^2s^2p^3s^3p^3d^4s^. Hoac vie't ggn la : [Ar] 3d^4s^. vay : \guV eii to la nhiing nguyen td ma nguyen tii cd electron cud'i ciing dugc di6n vao phan ldp s. Ngii> cn lo I la nhutig nguyen to ma nguyen tu cd electron cud'i ciing dugc didn vao phan ldp p. Ngu\ en lo cl la nhiing nguyen td ma nguyen tu cd electron cud'i ciing dugc dien vao phan ldp d. Nguyen to I la nhiing nguyen td ma nguyen tu cd electron cud'i ciing dugc didn vao phan ldp f. 2. Cau hinh electron nguyen tu ciia 20 nguyen to dau S6' electron Cau hinh electron z cua nguyen tur 1si 1 1s2 2 1s22s^ 3 1s22s2 4 1s22s22pi 5 1s22s22p2 6 1s22s22p3 7 1s22s22p'* 8 1s22s22p5 9 1s22s22p6 10 11 1s22s22p63s^ 12 1s22s22p63s2 13 1s22s22p63s23pi 14 1s22s22p63s23p2 15 1s22s22p63s23p3 16 1s22s22p63s23p'' 17 1s22s22p63s23p5 18 1s22s22p63s23p6 19 1s22s22p63s23p64si 20 1s22s22p63s23p64s2 26 Ten nguyen to hidro heli lit! beri bo cacbon nito oxi flo neon natri magie nhom silic photpho luu huynh clo agon kali canxi Ki hidu hoi hpe H He Li Be B C N 0 F Ne Na Mg Al Si P S Cl Ar K Ca LdpK (n = 1) 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 LdpL (n = 2) 1 2 3 4 5 6 7 8 8 8 8 8 8 8 8 8 8 8 Ldp M Ldp N (n = 3) (n = 4) 1 2 3 4 5 6 7 8 8 1 8 2 Cd thd' vid't cau hinh electron theo ldp. Thf du : Cau hinh electron cua Na la Is22s22p^3s' hay cd the dugc vie't theo ldp la 2, 8, 1. 3. Dac diem ciia ldp electron ngoai ciing - Dd'i vdi nguyen tu ciia ta't ca cac nguyen td, ldp electron ngoai cdng cd nhieu nha't la 8 electron. - Cac nguydn tu cd 8 electron d ldp electron ngoai ciing (ns^np^) va nguydn tii heli (Is^) khdng tham gia vao cac phan iing hoa hgc (trii trong mdt sd didu kien dac bidt) vi cau hinh electron ctia cac nguydn tu nay rat bdn. Dd la cac nguydn tir cua nguydn td khf hie'm. Trong tu nhien, phan tu khf hiem chi cd mdt nguydn tu. - Cac nguydn tu cd 1, 2, 3 electron d ldp ngoai ciing dd nhudng electron la nguydn tu ciia cac nguydn td kim loai (trii H, He va B). - Cac nguydn tu cd 5, 6, 7 electron d ldp ngoai ciing dd nhan electron thudng la nguydn tu cua nguydn td phi kim. - Cac nguydn tir cd 4 electron ngoai ciing cd the la nguyen tu ciia nguyen td kim loai hoac phi kim (xem bang tuan hoan). Nhu vay, khi biel eau hmh eleelmn eua nguyc;n li'r co the: dtr doan diro'c loai nguyen to. BAI TAP 1. Nguyen td cd Z = 11 thudc loai nguyen td A.s. B.p. C. d. D. f. Chpn dap an diing. 2. Ca'u hinh electron ciia nguyen tur luu huynh (Z = 16) la A. 1s22s22p53s23p5. B. 1s22s22p63s23p6. C. 1s22s22p63s23p4. D. 1s22s22p63s23p3. Chpn dap an diing. 27 3. Cau hinh electron cua nguyen td nhom (Z = 13) la 1s22s22p^3s23p''. Vay: A. Ldp thli nha't (Idp K) co 2 electron. B. Ldp thli hai (Idp L) co 8 electron. C. Ldp thd ba (Idp M) cd 3 electron. D. Ldp ngoai ciing cd 1 electron. Tim cau sai. 4. Tdng sd hat proton, ncrtron va electron trong nguyen tii cua mpt nguyen td la 13. a) Xac djnh nguyen tCr khdi. b) Viet ca'u hinh electron nguyen td cua nguyen to dd. (Cho biet : Cac nguyen td cd so hieu nguyen tCr tCr 2 de'n 82 trong bang tuan hoan thi 1<^<1,5.) 5. Co bao nhieu electron d Idp ngoai cung trong nguyen td cua cac nguyen td cd sd hieu nguyen td lan lUOt bang 3, 6, 9, 18 ? 6. Viet ca'u hinh electron nguyen tii ciia cac cSp nguyen td ma hat nhan nguyen td c6 sd proton la a) 1,3. b)8, 16. c) 7, 9. NhOrng nguyen td nao la kim loai ? La phi kim ? Vi sao ? 28 • Bai Li B«' LUY^N TA P : CAU TAO V6 NGUYEN TL/ Cling cd kie'n thiic ve : Thii tu cac phan lop electron theo chieu tang ciia nSng luong trong nguyen td ; Sd electron tdi da trong mot phan lop, mot lop ; Cau hinh electron ciia nguyen tu. Ren luyen kT nang xac dinh sd electron ciia cac lop va sd electron ldp ngoai ciing ciia nguyen tii 20 nguyen td dau trong bang tuan hoan, tu do suy ra tinh chat ca ban ciia nguyen td. A - KI^N THLTC CAN NA M VQN G Bang 3. Ldp va phan Idp electron So thiJrtirldp (n) Ten cua ldp So electron to! da So phan ldp Ki hieu phan Idp So electron toi da a phan ldp va a ldp 1 K 2 1 1s 2 2 L 8 2 2s, 2p 2, 6 8 3s, 2 3 M 18 3 3p, 3d 6, 10 18 4s, 2 4 N 32 4 4p, 4d, 4f 6, 10,14 32 Bang 4. Mdi lien he giua Idp electron ngoai cung vdi loai nguyen td nsV ns2 np^ , - Cau hinh electron „„ , „^2 „r,2 „c2 „„4 „* "^ "P ,. .. . ns'', ns'^ np'' ns'^ np'va ,,, ^ ,, Idp ngoai cung , . , % (He: Is'^) ns2 np^ ns'' np' So electron thuoc 1,2 hoac 3 4 5, 6 hoac 7 8 (2 6 He) Idp ngoai cung , .., kim loai c6 the la kim thudng lei ,u-u - Loa. nguySn to (trU H,He, B) toai hay phi kim phi kim ^^'^'^"^ CO the la tmh ., , , tuong doi tro ,, , .. thuong CO .- r,. . ,.'^ w«. kim loai hay .- . u-, • ve mat T nh chat co ban 4- u • • i • • 1 • u thuong co .- ^. ~— tmh kim loai kim loai hay . . ^... ve mat ^ua nguyen to tinh phi kim «'"h phi kim ^^^ ^-^^ B-BAITAP 1. The nao la nguyen td s, p, d, f ? 2. Cac electron thuoc Idp K hay Idp L lien ket vdi hat nhan chat che hon ? Vi sao ? 3. Trong nguyen td, nhiing electron ciia Idp nao quye't dmh tinh chat hoa hoc cua nguyen td nguyen td dd ? Cho thi du. 4. Vd cua mpt nguyen tCrco 20 electron. Hdi : a) Nguyen td dd cd bao nhieu Idp electron ? b) Ldp ngoai ciing co bao nhieu electron ? c) Nguyen td dd la kim loai hay phi kim ? 5. Cho biet sd electron tdi da d cac phan Idp sau : a) 2s ; b)3p ; c) 4s ; d) 3d. 6. Cau hinh electron ciia nguyen td photpho la 1s22s22p^3s23p'^. Hdi : a) Nguyen td photpho c6 bao nhieu electron ? b) Sd hieu nguyen td ciia photpho la bao nhieu ? c) Ldp electron nao c6 mdc nang lupng cao nha't ? d) Cd bao nhieu Idp electron, moi Idp cd bao nhieu electron ? e) Photpho la nguyen td kim loai hay phi kim ? Vi sao ? 7. Cau hinh electron ciia nguyen td cho ta bie't nhumg thong tin gi ? Cho thf du. 8. Viet ca'u hinh electron day dii cho cac nguyen td cd Idp electron ngoai cung la a) 2s^ ; b) 2s22p3 ; c) 2s22p6 ; d) 3s23p3 ; e) 3s23p5 ; g) 3s23p6. 9. Cho biet ten, ki hieu, sd hieu nguyen td ciia : a) 2 nguyen td ma nguyen td cd sd electron Idp ngoai cung la tdi da. b) 2 nguyen td ma nguyen td cd 1 electron d Idp ngoai ciing. c) 2 nguyen td ma nguyen td cd 7 electron d Idp ngoai ciing. 30 Chuang '^k {DOM[i{] m^ WiM \mM • Cac nguyen td duac sip xep vao bang tuan hoan theo nguyen tic nao ? • Mdi quan he giOa cau hmh electron nguyen tii cua nguyen td hoa hoc vdi vi tri cua nd trong bang tuan hoan. f/ Tinh chit cac nguyen td trong bang tuin hoan bien ddi nhu thi nao ? Bang tuan hoan cd y nghia gi ? 1 .'= « * ^ > ^-"-^^ S ^ A-/ / Dl. h/len-de-le-ep (Jl,. H. MendeAeee) (1834-1907) ^ ^ t^^S/ G^rt Ju^r ^^S6 X'^i'fy. ?c« a^itf ^*,.i> Z,^ij;( .^-^1 .9:tt St-=Jk' ."-/* -'Ts//' ^--//f .^^<; U)=.ari ai^,if^lf f^/)Si^^ 4i>=:/^r St^fi. j^=/i<# ^W/y 1^=/* / ^=J^. '&mtt. 4fr t»^ en td ma ngu> en tir cd cau hinh electron tuetng tu nhau. do do co tfnh chai hoa hoc gan gidng nhau va duoc xep thanh mot col. Bang tuan hoan cd 18 cot duoc chia thanh 8 nhdm A danh sd td IA dd'n VIIIA va 8 nhdm B danh sd tir IIIB dd'n VIIIB, rdi IB va IIB theo chieu tii trai sang phai trong bang tuan hoan (xem bang tuan hoan, trang 37). Mdi nhdm la mot cot, ridng nhdm VIIIB gdm 3 cot. Ngu\en tu cac ngu\en to trong ciing mot nhdm cd sd electron boa tri bang nhau \a bang so thu tu cua nhdm (trir hai cdt cud'i cua nhdm VIIIB). Ngoai each chia cac nguydn to thanh nhdm ngudi ta cdn chia chung thanh cac khd'i nhu sau : • Khdi cac ngu\en to s gdm cac nguydn td thudc nhdm IA (duoc goi la nhdm kim loai kiem) va nhdm HA (dugc goi la nhdm kim loai kidm thd). Thi du : Na (Z = 11) : Is22s22p63s' ; Mg (Z = 12) : Is22s22p63s2 ; Cac nguyen to s hoat ddng hoa hoc rat manh. cdn dugc ggi la cac kim loai hoat ddng. Chung cd khdi lugng ridng nhd, nhidt do ndng chay va nhidt do sdi tha'p hon hau hd't cac kim loai khae. • Kh(;>i cac ngti\ en to p gdm cac nguyen td thudc nhdm HIA dd'n nlidm VTTTA (trii He). Thi du : O (Z = 8) : ls-2s-2p'^; Ne (Z = 10) : Is22s-2p6 ; Nhdm .\ bao gdm cac ngu\en to s \a ngu\en to p, • Khoi cac ngu\ en to d gdm cac nguydn td thudc cac nhdm B. • Khoi ngu\ en to f gdm cac nguydn td xd'p d hai hang cud'i bang. Nhdm B bao s:6m cac neu\en lo d \a niiusen to (. .;34 3-HH10-C/B BAI TAP 1 • Cac nguyen td xep 6 chu ki 6 co sd Idp electron trong nguyen td la A. 3. B. 5. C. 6. D. 7. Chpn dap sd diing. 2. Trong bang tuan hoan cac nguyen td, sd chu ki nhd va sd chu ki Idn la A. 3 va 3. B. 3 va 4. C. 4 va 4. D. 4 va 3. Chpn dap sd diing. 3. So nguyen td trong chu ki 3 va 5 la A. 8va18. B. 18va8. C. 8 va 8. D. 18va18. Chpn dap sd diing. 4. Trong bang tuan hoan, cac nguyen td dupc sap xe'p theo nguyen tac nao ? A. Theo chieu tSng ciia dien tfch hat nhan. B. Cac nguyen td cd cung sd Idp electron trong nguyen td dupc xep thanh 1 hang. C. Cac nguyen to c6 cung sd electron hoa trj trong nguyen td dupc xep thanh 1 cdt. D. CaA, B, C. Chpn dap an diing nha't. 5. Tim cau sai trong cac cau sau day : A. Bang tuan hoan gdm cd cac d nguyen td, cac chu ki va cac nhom. B. Chu ki la day cac nguyen td ma nguyen td ciia chiing c6 cung so Idp electron, dupc sap xe'p theo chieu dien tfch hat nhan tSng dan. C. Bang tuan hoan co 7 chu ki. Sd thd tU cua chu ki bang sd phan Idp electron trong nguyen td. D. Bang tuan hoan cd 8 nhom A va 8 nhom B. 6. Hay cho bie't nguyen tac sap xep cac nguyen td trong bang tuan hoan cac nguyen td hoa hpe. 7. a) Nhdm nguyen td la gi ? b) Bang tuan hoan cac nguyen td cd bao nhieu cpt ? c) Bang tuan hoan cd bao nhieu nhom A ? d) Bang tuan hoan co bao nhieu nhom B ? Cac nhdm B gom bao nhieu cpt ? e) Nhiing nhdm nao chda nguyen td s ? Nhdng nhom nao chda nguyen td p ? NhCrng nhom nao chda nguyen td d ? 8. Hay cho bie't quan he gida sd thd tu cua nhdm A va sd electron hoa tn cua nguyen td cac nguyen to trong nhdm. 9- Hay cho bie't sd electron thudc Idp ngoai ciing cua nguyen td cac nguyen td Li, Be, B, C, N, O, F, Ne. Tu lieu DO I N^T V^ DI-MI-TRI l-VA-NO-VfCH MEN-O^L^^P VA OINH LUAT TUAN HOAN - BANG TUA N HOA N CAC NGUYEN T 6 HO A HQC Dinii-lri k\ ,i-iio-\ i( h ,\Un-(k'-le-e|.) sinh nf^dy 17 thang 1 nam 1834 o- thanh pho To-hon I liih(in\ki, Ironc; mt trong cac nguyen to do la nguvtm tcj 101 da ducrc dic?u che lan dau tit'n nam 19.S5 \a ducrc c\a\. ten ki mendelevi cic? to long kinh trong nha bae hoc Nga vi dai, \'\ix phat mmh ra dinh luat tiuin hoan \a bang tuan hoan cac nguyen tcr hoa hgc co gia tri to Icrn khong nhung etc")! vcri hoa hoc , m.i ( a dc)i vcri triei hoc , Thuyc't can lao nguven tir o \.he ki X,\ da seri sang vao dinh luat tuan hoan va bang tuan hoan e ae nguyen \c), tim ra nhieu dieu mcri me sau sac hern. Nhung lcri tii^n tri ciia ^\en-de;•-le•-('p "Dmh luat tuan hoan se khcrng bi dc doa pha vrr, ma chi co su bo sung va phat trie:'n ' eki e o nhirng bang chung tuyet vcri. 36 ChuW \ 1 2 3 IA 1 t m H UQ NUn M - 3 tM L i OM 1 11 turn N s Oin M M IIA 4' ••*'SM B S ijr B M ! 1 2 »,3< Mg in MigK BANG TUAN HOAN CACNGUYtNT6H0AH0C IIIA 5 10.81 B i,ot eo 3 1 3 20. H A l Mt IVA 8 12.01 C 2.SS Oton uHAn* 4,3,,21 0 tii , 1 4 20.09 Si i» ate VA 7 14,007 N 304 M B 31J34 5 15 30,87 P 2,19 nnpta VIA 8 15.99* 0 344 0 » 2 111? 1.3.1].; 1 6 32.03 S 2S0 U M huynh VIIA [H] 9 1BM3 F ,« no ., 17 35.4S C l 31« CB VIIIA 2 4Ma He 1 0 20.13 Ne N m iiW» < 1 8 39.95 Ar Ago n Mia^ ; 20 «Ma IIIB 21 44,96 IVB 2 2 47.90 VB 23 w,» VIB 2 4 Jv99e VIIB 2 5 54,M 2 6 55.65 VIIIB 27 58,93 2 8 s«,7i IB 2 9 63,54 MB 3 0 65.41 MiAp' 3 ^^^^ ^ W3« V 3|113[*I.5 IwiJi V 2 1II2M6 Ms/*' 1131*157 M>Ap* 4 19 mo K s« Kd IM*' C s ijo C u d D C 136 Sea ndi |Arl3l"'«'4p' 32 72,34 33 74.32 G e 2,01 A s 2.10 OcininJ Ann 14(Hl'W4p' |*lJl" 22* 6 -\ 1 3,5,7 8 6 12221 Rn Radon [)(tl«'*5(l%iV 141 7 87 IS ) Fr M Fund BWI. ' 8 8 226.03 R S M R M IM7 ^ 8 9 " I227I Ac , Actini iRrd 6(l'7»' 104 105 106 107 108 109 110 Kim loai -^—^ ^— > - Phi kim 1 3 • cac nguydn \6s H Cac nguydn to p • Cac nguyen to d • Cac nguyen to f Kl hlQu hoShpc NguyAn lii khoi Irung binh DA am dl^n Cdu hinh electron SiSotihOa Hg Lantan ** Hg Actini 5 8 140,12 C e .12 X«r1 |x»|4(Vai' 34 9 0 232.04 T h 3 Th«t IRHWVTI ' ' 5 9 140,91 Pr ,3 Prusotftm [Xt|4lV«i' 31 9 1 231,04 Pa ,s PfotacUm IRHS'M'/I ' 4,5 6 0 144,24 N d 11. NeodI m 1213,4 9 2 23a,D3 U .3. Unni IRnlSI*uV 131.* 151.6 6 1 11471 P m ,13 PromsU 3 9 3 (2371 Np u. N«|)1urK IHnlSI^W ,3i*.5 6 6 2 150,35 S m 1,17 Samarl IXiMfV^t' 23 9 4 12441 PU u. Plimmi IHnlSlV7i' I3M.56 6 3 151,93 Eu u EuropI [Xt|4l'S(^' 23 9 5 [243) A m 113 Arrwid IRi4Sl'si/Vi' [31,4,5 6 6 4 157,25 Gd u Gadoloni J 9 6 1247) C m lis Curl IRI^S|'M'7I' 3 65 ise.s3 Tb 1, TeU !Xa)4fS^ 34 9 7 1247) Bk ,3 BMM H IIWSVTI ' 3 ' 6 6 132,50 D y 122 Olproil 34 9 8 (2511 Cf u C«lltoni IBiilSl'V?,' 3 6 7 164,93 H o 123 Honmi 3 9 9 12521 ES U EMUnl |Flii|»"l)5t'V7i' 3 (•) So OXI hoa khong qhi daiu la s6 oxi hoci daanq • Bai Li Bai sy BIEN DOI TUAN HOAN CAU HINH ELECTRON NGUYEN TU CUA CAC NGUYEN TO HOA HOC Cau hinh electron nguyen tii cua cac nguyen to hoa hoc CO su bien doi tuan hoan khong ? Moi lien he giCra cau hinh electron nguyen tu vai tinh chat cua cac nguyen to trong chu ki va trong nhom A. I - SU BIEN OOl TUAN HOAN CAU HINH ELECTRON NGUYEN TU CUA CAC NGUYEN TO Bang dirdi day cho biet cau hinh electron ldp ngoai ciing ciia nguyen tir cac nguyen to nhom A. Bang 5. Cau hinh electron Idp ngoai cung cua nguyen tir cac nguyen to nhdm A IA H 1si Li 2si Na 3si K 45^ Rb 5si Cs 6si Fr 7si IIA Be 2s2 Mg 3s2 Ca 4s2 Sr 5s2 Ba 6s2 Ra 7s2 IIIA B 2s22pi Al 3s23pi Ga 4s24pi In 5s25pi Tl 6s26p^ IVA C 2s22p2 Si 3s23p2 Ge 4s24p2 Sn 5s25p2 Pb 6s26p2 VA N 2s22p3 P 3s23p3 As 4s24p^ Sb 5s25p3 Bl 6s26p3 VIA 0 2s22p'' S Ss^Sp" Se 4s24p'' Te Ss^Sp" Po 6s26p'' VIIA : ^ l F 2s22p5 Cl 3s23p5 Br 4s24p5 I 5s25p5 At 6s26p5 Vtll ^ He 1S2 Ne 2s22p6 Ar 3s23p6 Kr 4s24p6 Xe 5s25p6 Rn 6s26p6 Xet cau hinh electron nguyen tu ciia cac nguyen to trong bang 5 ta thay : D^u mdi chu ki la nguyen td cd cau hinh electron ldp ngoai ciing cua nguyen tu la ns'. Ket thiic mdi chu ki la nguyen td cd ca'u hinh electron ldp ngoai ciing ciia nguyen tu la ns^np^ (trir chu ki 1). Cau hinh electron ldp ngoai ciing cua nguyen tir cac nguyen td trong ciing mot nhdm A diroc lap di lap lai sau mdi chu ki, ta ndi rang : Chiing bien ddi mot cacli tuan hoan. Nhu the, .sir bien ddi tuan hoan ve cau hinh electron Idp ngoai ciing cua nguyen tii cac nguyen td khi dien tfch hat nhan tang dan chinh ia ngu\en nhan cua sir bien ddi tuan hoan tinh chat ciia cac ngu\en td. II - CAU HiNH ELECTRON NGUYEN TU CUA CAC NGUYEN TO NHOM A 1. Cau hinh electron lop ngoai ciing cua nguyen tii cac nguyen to nhom A a) Nguyen tu cac nguyen td trong ciing mot nhdm A cd ciing sd electron ldp ngoai ciing. Chfnh sir gidng nhau \'6 cau hinh electron ldp ngoai ciing cua nguyen tir la nguyen nhiln cua sir gidng nhau v6 tinh chat hoa hoc cua ciic nguyen td trong ciing mot nhdm A. b) Sd thu tir cua nhdm (IA, IIA...) cho biet sd electron d \&p ngoai ciling va ddng thdi ciing la so electron hoa tri trong nguyen tu cua cac nguyen td dd. c) Cac electron hoa tri ciia cac nguyen td thudc hai nhdm IA, IIA la electron s, cac nguyen to dd la cac nguyen to s. Cac electron hoa tri cua cac nguyen to thudc sau nhdm A tiep theo la cac electron s va p, cac nguyen td dd la cac nguyen td p (trir He). 2. Mot so nhom A tieu bieu a) Nhdm VIIIA la nhdm khf hiem, gom cac nguyen td ; heli, neon, agon, kripton, xenon va radon. Nguyen tu cua cac nguyen td trong nhdm (trii heli) ddu cd 8 electron d ldp ngoai ciing (cau hinh electron ldp ngoai ciing la ns-np^). Dd la cau hinh electron b6n viing. Hau het cac khi hiem deu khdng tham gia cac phan iing hoa hoc (trir mot sd trudng hop dac biet). O dieu kien thudng, cac khf hiem deu d trang thai khf va phan tir chi gdm mot nguyen tir. b) Nhom IA la nhom kiin loai kiem gom cac nguyen td : liti, natri, kali, rubidi. xesi (ngoai ra cdn cd nguyen td phdng xa franxi). Nguyen tir cua cac nguyen td kim loai ki6m chi cd 1 electron a ldp ngoai ciing (cau hinh electron ldp ngoai ciing la ns'). Vi vay, trong cac phan iimg hoa hoc, nguyen tir ciia cac nguyen td kim loai kiem cd khuynh hudng nhudng di 1 electron dt dat den cau hinh electron hin viing cua khf hiem. Do dd, trong cac hop chat, cac nguyen td kim loai kiem chi cd hoa tri 1. Cac kim loai kiem la nhirng kim loai dien hinh, thudmg cd nhiimg phan iimg sau : - Tac diing manh vdi oxi tao thanh cac oxit bazo tan trong nudc, thf du Lip , NajO,... - Tac dung manh vdi nudc a nhiet do thudng tao thanh hidro va hidroxit kiem manh, thf du NaOH. KOH,... - Tac dung vdi cac phi kim khae tao thanh mud'i, thi du NaCl, KjS,... c) Nhdm VIIA la nhdm halogen, gdm cac nguyen td : flo, clo, brom, iot (ngoai ra cdn cd nguyen td phdng xa atatin). Nguyen tir cua cac nguyen td halogen cd 7 electron d ldp ngoai cung (cau hinh electron ldp ngoai ciing la ns^np^). Vi vay, trong cac phan iimg hoa hoc, cac nguyen tir halogen cd khuynh hudng thu them 1 electron de dat den ca'u hinh electron ben viimg ciia khf hie'm. Do dd, trong cac hop chat vdi nguyen td kim loai, cac nguyen td halogen cd hoa tri 1. O dang dom chat, cac phan tir halogen gdm hai nguyen tir : F2, Clj, Br2, I2. Dd la nhumg phi kim dien hinh, thudng cd nhirng phan iimg sau : - Tac dung vdi kim loai cho cac mud'i nhu KBr, AICI3,... - Tac dung vdi hidro tao ra nhiimg hop chat khf HF, HCl, HBr, HI ; Trong dung dich nudc chiing la nhirng axit. - Hidroxit cua cac halogen la nhiimg axit, thf dii : HCIO, HCIO3. 40 BAI TAP 1. Cac nguyen td thuoc ciing mot nhom A c6 tinh chat hoa hoc tuong tu nhau, vi vo nguyen tCf cua cac nguyen to' nhom A cd A. so electron nhu nhau. B. so' Idp electron nhu nhau. C. so electron thuoc Idp ngoai cung nhU nhau. D. ciing sd electron s hay p. Chpn dap an diing. 2. Su bien thien tinh chat cua cac nguyen td thupc chu ki sau dupc lap lai tUPng tU nhu chu ki trudc la do : A. Su lap lai tfnh chat kim loai cua cac nguyen td d chu ki sau so vdi chu ki trudc. B. Su lap lai tinh chat phi kim cua cac nguyen to 6 chu ki sau so vdi chu ki trudc. C. Su lap lai ca'u hinh electron Idp ngoai ciing cua nguyen tCr cac nguyen td d chu ki sau so vdi chu ki trudc (d ba chu ki dau). D. Su lap lai tinh chat hoa hpe ciia cac nguyen td d chu ki sau so vdi chu ki trudc. Chpn dap an dung. 3. NhOmg nguyen td thudc nhdm A nao la cac nguyen td s, nguyen td p ? Sd electron thudc Idp ngoai ciing trong nguyen tCr ciia cac nguyen td s va p khae nhau the nao ? 4. Nhufng nguyen td nao dimg dau cac chu ki ? Cau hinh electron nguyen tCr ciia cac nguyen to dd cd dac diem chung gi ? 5. Nhiimg nguyen to nao dimg cudi cac chu ki ? Ca'u hinh electron ciia nguyen tu" cua cac nguyen td do cd dac diem chung gi ? 6. Mpt nguyen td d chu ki 3, nhdm VIA trong bang tuan hoan cac nguyen td hoa hpe. Hdi : a) Nguyen tif cua nguyen td dd cd bao nhieu electron d Idp electron ngoai ciing ? b) Cac electron ngoai ciing nam d Idp electron thir may ? c) Viet ca'u hinh electron nguyen tCf cua nguyen to tren. 7. Mdt sd nguyen td cd ca'u hinh electron cua nguyen tCr nhu sau : 1s22s22p4 ; 1s22s22p3; 1s22s22p63s23pi ; 1s22s22p63s23p5. a) Hay xac dinh sd electron hoa tri cua timg nguyen tif. b) Hay xac dinh vj tri cua chung (chu ki, nhdm) trong bang tuan hoan cac nguyen td hoa hpe. • Bai Li Bai sy BIEN OOl TUAN HOAN TINH CHAT CUA CAC NGUYEN TO HOA HOC OINH LUAT TUAN HOAN Theo chi^u tang dien tich hat nhan ciia nguyen tir cac nguyen to : • Tinh kim loai va phi kim ciia cac nguyen td bie'n doi ra sao ? • Hoa trj ciia cac nguyen td co thay doi theo quy luat nao khong ? • Thanh phSn va tinh chat ciia hop chat cac nguyen td bien doi nhu'the nao ? I - TINH KIM LOAI, TINH PHI KIM Tinh kim loai la tfnh chat cua mot nguydn td ma nguyen tir ciia nd de mat electron de' trd thanh ion ducmg. Nguyen tir cang de mat electron, tinh kim loai cua nguyen to cang manh. linh phi kim la tinh chat cua mot nguyen to ma nguyen tir cua nd dl thu electron de trd thanh ion am. Nguyen tir cang de thu electron thi tfnh phi kim ciia nguyen to cang manh. Ranh gidi tucmg ddi giira nguyen to kim loai, phi kim trong bang tuan hoan cac nguyen to hoa hoc (trang 37) duoc phan each bang dudmg dfch dac in dam. Phfa phai la cac nguyen td phi kim, phfa trai la cac nguydn to kim loai. 1. Sir bien doi tinh chat trong mot chu ki Trong mot chu ki. theo chieu tang dim ciia dien tich hat nhan, tfnh kim loai cua Ciic nguyen td yeu dan. ddng thdi tinh phi kim manh dan. Thi du : Chu ki 3 bat dau tir nguyen td Na (Z = 11), [Ne]3s', la mot kim loai dien hinh. Rdi lan lugt den Mg (Z = 12), [Ne]3s2, la kim loai manh nhung hoat ddng kem natri. Al (Z = 13), [Ne]3s'^3p', la mdt kim loai nhung hidroxit da cd tfnh chat luomg tfnh. Si (Z = 14), [Ne]3s23p2 la mdt phi kim. Tir P (Z = 15), [Ne]3s23p'' den S (Z = 16), [Ne]3s23p'* tfnh phi kim manh dan. Cl (Z = 17), [NeJSs^Sp-'', la mdt phi kim dien hinh, rdi den khf hie'm Ar (Z = 18), [Ne]3s23p^. Quy luat tren dugfc lap lai dd'i vdi mdi chu ki. Cd the giai thich quy luat bid'n ddi tfnh chat trdn theo ban kfnh nguyen tir: Trong mot chu ki. khi di tir trai sang phai, dien tich hat nhan tang dan nhumg sd ldp electron cua nguydn tir cac nguydn td bang nhau, do dd luc hut ciia hat nhan vdi cac electron ldp ngoai ciing tang ldn lam cho ban kfnh nguyen tir giam dan (xem hinh 2.1), ndn kha nang dd nhuiimg electron (dac trirng cho tinh kim loai ciia nguyen td) giam diin. ddng thdi kha nang thu electron (dac trung cho tinli phi kim ciia nguyen td) tang diin. IA IIA IIIA IVA VA VIA VIIA A ^ /Si ^ ift. p (Pi 0,123 0,089 0,080 0,077 0,070 0,066 0,064 ^P 0 ^ 0 © o o ® o 0,157 0,136 0,125 0,117 0,110 0,104 0,099 0,125 0,117 0,110 0,104 0,099 0 ^ ^ ^ ^ 0,125 0,122 0,121 0,117 0,114 0,203 0,174 0,125 0,122 0,121 0,117 0,114 ^p @ © s ^ © o 0,216 0,191 0,150 0,140 0,140 0,137 0,133 ^ Chieu giam dan cua ban kinh nguyen ttf Hinh 2.1. Ban kinh nguyen td cCia mqt so nguyen to (nm) Trong mdi chu ki, ban kinh nguyen tCl giam tit trai qua phai. Trong mdi nhom A, ban kinh nguyen tCt tang theo chieu tit tren xud'ng dudi. 2. Su bien doi tinh chat trong mot nhom A Trong mot nhdm A. theo chieu tang ciia dien tfch hat nhan. tfnh kim loai cua cac nguyen td manh ddn. ddng thdi tinh phi kim yeu dan. Thi du : Nhdm IA gdm cac kim loai dien hinh : Tinh chat kim loai tang rd ret tir Li (Z = 3), ls22s' dd'n Cs (Z = 55), [Xe]6s' tiic la kha nang mat electron tang dan. Xesi la nguydn td kim loai manh nhat. Nhdm VIIA gdm cac phi kim dien hinh : Tfnh phi kim giam dan tir F (Z = 9), Is22s22p-'^ dd'n I (Z = 53), [Kr] 4d'05s25p5, turc la kha nang thu them electron giam dSn. Flo la nguyen td phi kim manh nhat. Quy luat dd dugc lap lai dd'i vdi cac nhdm A khae va dugc giai thfch nhu sau : Trong mdt nhdm A, theo chieu tir trdn xud'ng dudi, didn tfch hat nhan tang, nhung ddng thdi sd ldp electron cung tang lam ban kfnh nguyen tu cac ngu\ en to tiing nhanh va chiem uu the hmi ndn kha nang nhudng electron ciia cac nguyen to cang tang ldn - tfnh kim loai tang va kha nang nhan electron cua cac nguydn to giam - tfnh phi kim giam. Nguydn tir Cs cd ban kfnh nguyen tir ldn nhat ndn dd nhudng electron hom ca, nd la kim loai manh nhat. Nguyen tir F cd ban kfnh nguydn tir nhd nhat ndn dd thu them electron hom ca, nd la phi kim manh nha't. 3. Dp am dien a) Khdi niem Do am dien ciia mot nguyen tir dac tnmg cho kha nang hiit electron ciia nguyen tir dd khi hinh thanh lien kei hoa hgc. Nhu vay, do am dien ciia nguyen tir cang ldn thi tfnh phi kim cua nd cang manh. Ngugc lai, do am dien cua nguydn tir cang nhd thi tfnh kim loai cua nd cang manh. b) Bdng dp dm dien Trong hoa hgc, cd nhidu thang do am dien khae nhau do cac tac gia tfnh toan tren nhCrng co sd khae nhau. Dudi day gidi thieu bang gia tri do am dien do nha hoa hgc Pau-linh (Pauling) thid't lap nam 1932. Vi nguydn td flo la phi kim manh nha't, Pau-linh quy udc lay do am didn ciia nd de xac dinh do am didn tucmg dd'i cua cac nguydn tir nguyen to khae. Hinh 2.2. Nha hoa hqc ngudi Mf Pau-linh (L.C. Pauling, 1901-1994) giai thudng Nd-ben Hoa hqc nam 1954, giai thudng Nd-ben Hoa binh nam 1962 Bang 6. Gia tri do am dien cua nguyen tumdt so nguyen to nhdm A theo Pau-linh Li 0,98 Na 0.93 K 0,82 Rb 0,82 Cs 0,79 Be 1.57 Mg 1,31 Ca 1,00 Sr 0,95 Ba 0,89 B 2,04 Al 1.61 Ga 1.81 In 1.78 TI 1,62 C 2,55 Si 1,90 Ge 2,01 Sn 1,96 Pb 2.33 N 3,04 P 2,19 As 2,18 Sb 2.05 Bi 2,02 O 3,44 S 2,58 Se 2,55 Te 2.1 Po 2.0 F 3,98 Cl 3,16 Br 2.96 I 2.66 At 2,2 Trong mdt chu ki, khi di tir trai sang phai theo chidu tang cua didn tfch hat nhan, gia tri do am dien ciia cac nguyen tir ndi chung tang ddn. Trong mdt nhdm A. khi di tir trdn xudng dudi theo chidu tang cua didn tfch hat nhan, gia tri do dm dien cua cac nguyen tir ndi chung giam ddn, Quy luat bid'n doi do am didn phii hgp vdi su bid'n ddi tfnh kim loai, tfnh phi kim cua cac nguydn to trong mdt chu ki va trong mdt nhdm A ma ta da xet d trdn. Kd't luan : Tinh kim loai, tfnh phi kim ciia cac ngu\en td bien ddi tudn hodn theo chidu tang ciia dien tfch hat nhan. II - HOA TR! CUA CAC NGUYEN T 6 Trong mdt chu ki, di tir trai sang phai, hoa tri cao nhat ciia cac nguydn to trong hgp chat vdi oxi tang Mn lugt tir 1 ddn 7, cdn hoa tri cua cac phi kim trong hgp chSit vdi hidro giam tir 4 dd'n 1. Thf du, trong chu ki 3, ba nguydn td dSu chu ki (Na, Mg, Al) tao thanh hgp chd't oxit, trong dd chiing cd hoa tri ldn lugt la 1, 2, 3. Cac nguydn td tid'p theo (Si, P, S, Cl) cd hoa trj ldn lugt la 4, 5, 6, 7 trong oxit cao nhdt. m^ Cac nguydn td phi kim Si, P, S, Cl tao dugc hgp chat khf vdi hidro, trong do chiing cd hoa trj lan lugt 4, 3, 2, 1. Dd'i vdi cac chu ki khae, su bien ddi hoa tri cua cac nguydn td cung didn ra tuong tu (xem bang 7). Bang 7. Subien ddi tuan hoan hoa tri cua cac nguyen to Sothurt^r nh6m A Hop chat vdi oxi Hoa tri cao nha't v6i oxi Hop chat khi v6i hidro Hoa tri v6i hidro IA Na20 KjO 1 IIA MgO CaO 2 IIIA AI2O3 68203 3 IVA SiOj Ge02 4 SiH4 GeH^ 4 VA P2O5 AS2O5 5 PH3 ASH3 3 VIA SO3 Se03 6 H2S H2Se 2 VIIA CI2O7 8^207 7 HCl HBr 1 III - OXIT VA HIDROXIT CUA CAC NGUYEN T 6 NH6 M A THUOC CUNG CHU Kl Trong mdt chu ki, di tir trai sang phai theo chidu tdng cua didn tfch hat nhan, tfnh bazo cua cac oxit va hidroxit tuomg umg yd'u dan, ddng thdi tfnh axit cua chiing manh dan. Bang 8. Subien ddi tinh axit - bazo 111 III AljOj SiOj P2O5 S63 Oxit OxH Oxit Oxit ludng tinh axit axit axit CljO, Oxit axit NaOH Bazd manh (kiem) Mg(0H)2 Baza yeu AI(0H)3 Hidroxit li/dng tinh H2Si03 Axit yeu H3PO4 Axit trung binh H2SO4 Axit manh HCIO4 Axit rat manh Tinh baza yeu dan ddng thdi tinh axit manh dan Sir bid'n ddi tfnh chd't nhu the dugc lap lai d cac chu ki sau. IV - DjNH LUAT TUAN HOAN Trdn co sd khao sat su bid'n ddi tuan hoan cua cau hinh electron nguydn tir, ban kfnh nguydn tir, do am dien cua nguyen tir, tfnh kim loai va tfnh phi kim ciia cac nguyen td hod hgc, thanh phan va tfnh chat cdc hgp chat ciia chiing, ta thdy tfnh chat ciia cac nguydn td hoa hgc bid'n ddi theo chieu didn tfch hat nhdn tang, nhung khdng lidn tuc ma tuan hoan. Dinh luat tuan hoan vd cac nguydn td hoa hgc dugc phat bieu nhu sau : Tfnh chat cua cac nguyen td va dom chat, cimg nhu thimh phan va tinh chat cua cac hgp chdi tao nen tir cac nguyen td dd bien doi tuan hoiin theo cliieu limg cua dien tich hat nhan nguyen tir. BAI TAP 1. Trong mot chu ki, ban kinh nguyen tif cac nguyen td A. tang theo chieu tang dan ciia dien tich hat nhan, B. giam theo chieu tang dan ciia dien tfch hat nhan. C. giam theo chieu tang ciia tinh phi kim. D. B va C deu dimg. Chon dap an dimg nha't. 2. Trong mot nhdm A, ban ki'nh nguyen tif ciia cac nguyen td : A. tang theo chieu tang ciia dien tich hat nhan. B. giam theo chieu tang cua dien tich hat nhan. C. giam theo chieu giam cua tinh kim loai. D. A va C deu dimg. Chon dap an dimg nha't. 3. Nhiimg tinh chat nao sau day bie'n doi tuan hoan ? a) Hoa tri cao nhat vdi oxi. d) Sd Idp electron. b) Nguyen tif khdi. e) Sd electron trong nguyen tif. c) Sd electron Idp ngoai cimg. 4. Cac nguyen td halogen dugc sap xe'p theo chieu ban kinh nguyen tif giam dan (ti/ trai sang phai) nhU sau : A. 1, Br, Cl, F, C, I, Br, F, Cl. B. F, Cl, Br, I. D. Br, I, Cl, F. Chon dap an dimg. 5. Cac nguyen td ciia chu ki 2 dugc sap xe'p theo chieu gia tri do am dien giam dan (tir trai sang phai) nhu sau : A. F, O, N, C, B, Be, Li. B. Li, B, Be, N, C, F, O. C. Be, Ll, C, B, O, N, F. D. N, O, F, Li, Be, B, C. Chpn dap an dimg. 6. Oxit cao nha't ciia 1 nguyen td R img vdi cdng thifc RO2. Nguyen td R dd la A. Magie. B. Nito. C. Cacbon. D. Photpho. Chpn dap an dimg. 7. Theo quy luat bien ddi tinh chat dOn chat ciia cac nguyen td trong bang tuan hoan thi A. phi kim manh nha't la iot. B. kim loai manh nha't la liti. C. phi kim manh nha't la flo. D. kim loai ye'u nha't la xesi. Chon dap an dung. 8. Viet ca'u hinh electron cua nguyen tif magie (Z = 12). Oe dat dugc ca'u hinh electron cue nguyen tif khi hie'm gan nha't trong bang tuan hoan, nguyen tif magie nhan hay nhudng bao nhieu electron ? Magie the hien tinh chat kim loai hay phi kim ? 9. Viet ca'u hinh electron ciia nguyen tif lUu huynh S (Z = 16). De dat dUOc ca'u hinh electron ciia nguyen tif khi hie'm gain nha't trong bang tuan hoan, nguyen tif luu huynh nhan hay nhudng bao nhieu electron ? Luu huynh the hien tinh chat kim loai hay phi kim ? 10. Do am dien ciia mdt nguyen tif la gi ? Gia tn dp am dien ciia cac nguyen tif trong cac nhdm A bie'n ddi nhU the nao theo chieu dien tich hat nhan tang ? 1 1 . Nguyen tif nao trong bang tuan hoan cd gia trj dp am dien Idn nha't ? Tai sao ? 12. Cho hai day chat sau : Li20 BeO B2O3 CO2 N2O5 CH4 NH3 H2O HF Xac djnh hoa tri ciia cac nguyen td trong hop chat vdi oxi va vdi hidro. 448 I Bai Y NGHiA CUA BANG TUAN HOA N L I O CAC NGUYEN T 6 HOA HOC • Vi trf cua mpt nguyen td trong bang tuan hoan cho ta cac thong tin gi ve nguyen td dd ? • Ngugc lai, khi bie't sd hieu nguyen tir ciia mpt nguyen td ta CO the suy ra vi trf ciia no trong bang tuan hoan dupc khong ? I - QUAN H^ GIUA Vj TRI CUA NGUYEN T 6 vA CAU TAO NGUYEN TU CUA NO Bid't vi trf ciia mdt nguydn to trong bang tudn hoan, cd the suy ra cd'u tao nguydn tir cua nguydn to dd va ngugc lai (xem so dd sau) : Vi tri ciia mot nguyen to trong Cau tao nguyen tur bang tuan hoan (6) -se! thif tu ciia nguy§nt6 ^^ - Sfi proton, sfi electron - S6 thif tu ciia chu ki - s616p electron - S6 thif tu ciia nhom A - S6 electron I6p ngo^i cung Thi du /. Bid't nguydn td cd sd thii tu la 19 thugc chu ki 4, nhdm IA, cd the suy ra : Nguyen tir ciia nguyen td dd cd 19 proton, 19 electron. Nguydn tir dd cd 4 ldp electron (vi sd ldp electron bang sd thii tu ciia chu ki). Cd 1 electron d ldp ngoai ciing (vi so electron ldp ngoai ciing bang sd thiir tir ciia nhdm A). Dd la nguydn to kali. Thi du 2. Bid't cd'u hinh electron nguyen tir cua mdt nguydn to la ls^2s^2p^3s^3p'^ cd th^ suy ra : Tdng sd electron ciia nguydn tir dd la 16, vay nguydn td dd chid'm d thiir 16 trong bang tudn hoan (vi nguydn tir cd 16 electron, 16 proton, sd dem vi didn tfch hat nhdn la 16, bang sd thii tu ciia nguydn td trong bang tudn hoan). Nguydn td dd thudc chu ki 3 (vi ed 3 ldp electron), thudc nhdm VIA (vi cd 6 electron ldp ngoai eiing). Dd la nguydn td luu huynh. 4-HH10-C/A 4 9 II - QUAN Ht GIUA Vj TR[ vA TINH CHAT CUA NGUYEN l6 Bid't vi trf ciia mdt nguyen td trong bang tuan hoan, cd the suy ra nhiing tfnh chd't hod hgc co ban ciia nd : - Tfnh kim loai, tfnh phi kim : Cac nguydn td d cdc nhdm IA, IIA, IIIA (trii hidro va bo) cd tfnh kim loai. Cac nguydn td d cac nhdm VA, VIA, VIIA (trir antimon, bitmut va poloni) cd tfnh phi kim. - Hod tri cao nhd't ciia nguyen td trong hgp chat vdi oxi, hoa tri cua nguydn td trong hgp chat vdi hidro. - Cdng thurc oxit cao nhdt. - Cdng thiic hgp chdt khf vdi hidro (nd'u cd). - Cdng thtic hidroxit tuomg iing (ndu cd) va tfnh axit hay bazo cua chiing. Thi du : Nguyen td luu huynh a 6 thii 16, nhdm VIA, chu ki 3. Suy ra : luu huynh la phi kim. Hoa tri cao nhd't vdi oxi la 6, cdng thiic oxit cao nhd't la SO3. Hod tri vdi hidro la 2, cdng thiic hgp chd't khi vdi hidro la HjS. SO3 la oxit axit va H2SO4 la axit manh. - SO SANH TfNH CHAT HOA HOC CUA MO T NGUYEN T 6 v6i cAc NGUYEN T 6 LAN CAN Dua vao quy ludt bid'n ddi tfnh chd't cua cac nguydn td trong bang tudn hoan cd the so sanh tinh chat hoa hgc cua mdt nguyen to vdi cac nguydn td ldn can. Thi du : So sanh tfnh chat hoa hgc cua P (Z = 15) vdi Si (Z = 14) va S (Z = 16), vdi N (Z = 7) va As (Z = 33). Trong bang tuan hoan, cac nguydn td Si, P, S thudc cung mdt chu ki. Nd'u xd'p theo chieu dien tfch hat nhdn tang dan ta dugc day Si, P, S. Trong chu ki, theo chieu dien tfch hat nhan tang thi tfnh phi kim tang. Vdy, P cd tfnh phi kim yd'u hom S va manh hom Si. Trong nhdm VA, theo chieu didn tfch hat nhan tang ddn, ta cd day N, P, As, tinh phi kim giam dan. P cd tfnh phi kim kem hom N va manh hem As. Vay P cd tfnh phi kim ydu hom N va S, hidroxit cua nd la H^PO^ cd tfnh axit yd'u hon HNO3 va H2SO4. I K 4-HHIO-C/B BAI TAP 1. So hieu nguyen tif Z cua cac nguyen td X, A, M, Q lan lugt la 6, 7, 20, 19. Nhan xet nao sau day dimg ? A. X thuoc nhdm VA. C. M thudc nhdm IIB. B. A, M thudc nhdm IIA. D. Q thudc nhdm IA. 2. Sd hieu nguyen tuf Z ciia cac nguyen td X, A, M, Q lan lugt la 6, 7, 20, 19. Nhan xet nao sau day dimg ? A. Ca 4 nguyen td tren thupc 1 chu ki. C. A, M thudc chu ki 3. B. M, Q thudc chu ki 4. D. Q thudc chu ki 3. 3. Trong bang tuan hoan, nguyen td X cd sd thir tu 16, nguyen td X thudc A. chu ki 3, nhdm IVA. C. chu ki 3, nhdm VIA. B. chu ki 4, nhdm VIA. D. chu ki 4, nhdm IIIA. Chon dap an dimg. 4. Dua vao vj tri ciia nguyen td Mg (Z- 12) trong bang tuan hoan, a) Hay neu cac tinh chat sau ciia nguyen td : - Tinh kim loai hay tinh phi kim. - Hoa trj cao nha't trong hgp chat vdi oxi. - Cdng thifc ciia oxit cao nha't, ciia hidroxit tuong irng va ti'nh chat ciia nd. b) So sanh tinh chat hoa hoc ciia nguyen td Mg (Z = 12) vdi Na (Z = 11) va Al (Z = 13). 5. a) Dua vao vi tri ciia nguyen td Br (Z = 35) trong bang tuan hoan, hay neu cac tinh chat sau : - Tinh kim loai hay tinh phi kim. - Hoa tri cao nha't trong hgp chat vdi oxi va vdi hidro. - Cdng thirc hgp chat khi ciia brom vdi hidro. b) So sanh tinh chat hoa hgc ciia Br vdi Cl (Z = 17) va I (Z = 53). 6. Dua vao quy luat bie'n ddi tinh kim loai, tinh phi kim ciia cac nguyen td trong bang tuan hoan, hay tra Idi cac cau hdi sau : a) Nguyen td nao la kim loai manh nha't ? Nguyen td nao la phi kim manh nhat ? b) Cac nguyen td kim loai dugc phan bd 6 khu vuc nao trong bang tuan hoan ? c) Cac nguyen td phi kim dugc phan bd d khu vUc nao trong bang tuan hoan ? d) Nhdm nao gdm nhOmg nguyen td kim loai dien hinh ? Nhdm nao gdm hau het nhumg nguyen td phi kim dien hinh ? e) Cac nguyen td khi hie'm nam 6 khu vUc nao trong bang tuan hoan ? 7. Nguyen td atatin At (Z = 85) thuoc chu ki 6, nhdm VIIA. Hay dU doan tfnh chat hoa hgc CO ban ciia nd va so sanh vdi cac nguyen td khae trong nhdm. li • BaBai i LUY^N TAP : BANG TUAN HOAN, su BI^N 061 TUA N HOA N CAU HINH ELECTRON NGUYEN TU vA TINH CHAT CUA CAC NGUYEN T 6 HO A HQC • Ciing CO kien thuc ve : Cau tao cua bang tucin hoan cac nguyen to hoa hpe. Su bien doi tuan hpan cau hinh electron nguyen tir ciia cac nguyen td, tinh kim loai, tinh phi kim, ban kinh nguyen tir, dp am dien, hoa trj va dinh luat tuan hoan. • Ren luyen kT nang lam bai tap ve mdi quan he giua vi tri, cau tap nguyen tir va tinh chat ciia nguyen td. A - KI^N THLTC CAN NA M VQN G 1. Cau tao bang tuan hoan a) i\guyen tdc sdp xep cdc nguyen td trong bang tudn hodn - CAc nguydn td dugc sdp xd'p theo chieu tang ddn cua didn tich hat nhdn. - Cae nguyen td cd cim 7 sd ldp electron trong nguydn tir dugc xd'p thanh mdt hang. - Cac nguyen td cd sd' electron hoa tri nhu nhau dugc xep thanh mdt cdt. b) O nguven id : Mdi nguyen td xd'p vao mdt d. c) Chu ki - Mdi hang la 1 chu ki. - Bang cd 7 chu ki: 3 chu ki nho (chu ki 1, 2, 3) va 4 chu ki ldn (chu ki 4, 5, 6,7). - Nguydn tir cae nguydn td thudc mdt chu ki cd sd ldp electron nhu nhau. - Sd thli tu cua chu ki bang sd ldp electron cua nguydn tit cac nguyen td trong chu ki dd. df Cac nhdm A (tir IA dd'n VIIIA) gdm eae nguyen td d chu ki nhd va chu ki ldn. Cac nguydn td nhdm IA, IIA la nguydn td s, cac nguydn td t^ nhdm IIIA dd'n VniA la nguydn td p. Cac nhdm B (tir IIIB dd'n VIIIB rdi IB va IIB theo chidu tir trai sang phai trong bang he thdng tuan hoan) ehi gdm cac nguyen td d chu ki ldn. Cac nguyen td thudc nhdm B la cdc nguydn to d va f. H 2. Sir bien doi tuan hoan a) Cdu hinh electron cua nguyen tu Sd electron ldp ngoai cung ciia nguydn th cac nguyen td d mdi chu ki tang tir 1 den 8 thudc cac nhdm tuf IA dd'n VIIIA. Cd'u hinh electron nguydn tir ciia cac nguydn td bid'n ddi tudn hoan. b) Su bien doi tudn hodn tinh kim ioai, tinh phi kim, bdn kinh nguyen tu vd gid tri dp dm dien cua cdc nguyen to dupc tdm tdt trong bdng sau : ^ \ ^ Chu ki Ntiom A ^'\ ^ '2 . Ban kinh nguyen til 1 c , >. 3 O) c .c ,c c •§• t .i 1 Tinh kim loai E J£ c m Tint •ra •Q. Gia tri do am dien p Tinh phi kim Chu thich : Chieu mui ten la chieu tSng. 3. Djnh luat tuan hoan Tfnh cha't ciia cac nguydn td va don chd't, cung nhu thanh phdn va tfnh chd't cua cac hgp chd't tao ndn tiT cac nguydn to dd bid'n doi tudn hoan theo chieu tang cua didn tfch hat nhan nguydn tu. B - BAI TAP 1- a) can cif vao dau ma ngudi ta xe'p cac nguyen to thanh chu ki, nhdm ? b) The nao la chu ki ? Bang tuan hoan cd bao nhieu chu ki nho, bao nhieu chu ki Idn ? Moi chu ki cd bao nhieu nguyen td ? 2. Tim cau sai trong nhCmg cau dudi day : A. Trong chu ki, cac nguyen td dUdc xe'p theo chieu dien tich hat nhan tang dan. B. Trong chu ki, cac nguyen td duoc xe'p theo chieu sd hieu nguyen tif tang dan. C. Nguyen tir ciia cac nguyen td trong ciing mdt chu ki cd sd electron bang nhau. D. Chu ki thudng bat dau la mot kim loai kiem, ket thiic la mgt khf hiem (trir chu ki 1 va chu ki 7 chua hoan thanh). S3 3. Jii trai sang phai trong mdt chu ki, tai sao ban kinh nguyen tuf cac nguyen td giam thi tinh kim loai giam, tinh phi kim tang ? 4. Trong bang tuan hoan, cac nhdm A nao gom hau he't cac nguyen to kim loai, nhdm A nao gom hau he't cac nguyen td phi kim, nhdm A nao gdm cac nguyen td khi hiem ? oac diem sd electron Idp ngoai ciing cua cac nguyen tuf trong cac nhdm tren. 5. Tong so hat proton, notron, electron cua nguyen tif cua mdt nguyen td thudc nhdm VIIA la 28. a) Tinh nguyen tif khd'i. b) Viet ca'u hinh electron nguyen tif ciia nguyen td do. 6. Mdt nguyen td thudc chu ki 3, nhdm VIA trong bang tuan hoan. a) Nguyen tuf cua nguyen td dd cd bao nhieu electron d Idp electron ngoai cimg ? b) Ldp electron ngoai ciing la Idp electron thir may ? c) Viet sd electron 6 timg Idp electron. 7. Oxit cao nha't ciia mgt nguyen td la RO3, trong hgp chat ciia nd vdi hidro cd 5,88% H ve khd'i lugng. Xac dinh nguyen tif khdi ciia nguyen td dd. 8. Hgp chat khi vdi hidro cuia mdt nguyen to la RH^. Oxit cao nha't cua nd chifa 53,3% oxi ve khdi lugng. Tim nguyen tif khd'i ciia nguyen to dd. 9. Khi cho 0,6 g mdt kim loai nhdm IIA tac dung vdi nudc tao ra 0,336 lit khi hidro (d dieu kien tieu chuan). Xac djnh kim loai dd. S^-: Chuang J N J LA:^ »^ Vi sao nguyen tu cac nguyen td (tni khi hiim) cd xu hudng Uen kit vdi nhau tao thanh phan tti hay tinh the ? ^ Cd miy Ioai lien kit hoa hoc ? Cac nguyen tvt lien kit vai nhau nhu thS nao ? C6 thS hiSu mdt each dan gian, lien kit hoa hoc li su kit h Li+ + e Thi du 2 : Cac nguyen tir kim loai, ldp ngoai ciing cd 1, 2, 3 electron deu dd nhudng electron de trd thanh ion duomg. Na ^—> Na"^ + e Mg —> Mg2+ + 2e Al > Al3+ + 3e Cac cation kim loai dugc ggi theo tdn kim loai. Thf du, Na+ ggi la cation natri. 56 c) Trong cac phan iing hod hgc, d^ dat ca'u hinh electron bdn cua khf hidm, nguydn tir phi kim cd khuynh hudng nhdn electron tir nguydn tir cac nguyen td khae trd thanh MMI .I;;I, ggi la .mioii. Thi du I : Su tao thanh ion florua (F~) tif nguydn tir F (Z = 9). Cd'u hinh electron ciia nguydn tir F la \^'^2^^2^^ hay (2, 7), ldp ngoai ciing cd 7 electron dd nhan thdm 1 electron trd thanh ion dm (hay anion) florua (F ~), Is22s22p^ hay (2, 8). Cd thd' bieu didn qua trinh trdn bang phucmg tiinh sau : F (2,7) F- (2,8) F + le —> F Thi du 2 : Nhumg nguydn tir phi kim ldp ngoai ciing cd 5, 6, 7 electron (ns^np^, ns^p'* hay ns^np^) cd kha nang nhan thdm 3, 2 hay 1 electron dd trd thanh ion am (hay anion). Cl + le —> C\- O + 2e —> 02- Cac anion phi kim dugc ggi theo tdn gd'c axit (trir O^" ggi la anion oxit). Thi du : F~ ggi la anion florua. 2, Ion don nguyen tu va ion da nguyen tti a) Ion dem nguyen tir la cac ion tao ndn tir mdt nguydn tir. Thf du : cation Li+, Na"^, Mg2+, AP + va anion F", S^". b) Ion da nguydn tir la nhiing nhdm nguydn tir mang didn tfch duomg hay am. Thf du : cation amoni NH+ , anion hidroxit OH", anion sunfat SO^". 57 II - s u TAO THAN H LI^N K^T ION Di hidu dugc su tao thanh lidn kdt ion, ta xet phan iing cua natri vdi clo : Nguydn tir Na (ls-2s^2p^3s') nhudng 1 electron cho nguydn tir Cl (ls-2s-2p^3s23p^) dd bid'n ddi thanh cation Na+ (Is22s22p^), ddng'thdi nguyen tir clo nhan 1 electron ciia nguydn tir Na de bidn ddi thanh anion c r (1 s-2s22p^3s23p^), ed the bieu didn qua trinh trdn nhu sau : Na(2. 8. 1) Cl(2, 8, 7) Na+ (2, 8) cr (2, 8, 8) Na + Cl -^ Na+ + Cr Hai ion dugc tao thanh mang didn tfch ngugc da'u hiit nhau bdng lire hiit tinh dien, tao nen phan tir NaCl : Na+ + Cl- —^ NaCl Lien ket giiia cation Na"^ va anion Cr la lien kdt ion. Vay, li^ 11 1^^^"' i'^'i 1^1 lit"n ^'^l dugc hinli tlianli boi iuc iiiii linh dicn guia cac ion nianu iliv-'ii Iich irai i.lau. Phan ling hod hgc trdn cd thd dugc bidu didn bdng phuomg trinh hod hge sau : 2 X le I I 2Na + Cl2 —> 2Na+Cr III - TINH TH^ ION \. Tinh the NaCl CJ the rdn, NaCl tdn tai dudi dang tinh thd ion. Trong mang tinh thd NaCl, cac ion Na"^ va C\~ dugc phdn bd ludn phidn deu dan trdn cac dinh ciia cac hinh lap phuomg nhd. Xung quanh mdi ion deu cd 6 ion ngugc dd'u gdn nhd't (xem hinh 3.1). 58 ^ ci m Na"- A- ^ -^7 I / y»- -/• • ">» / -7* / y* / • # ^ Hinh 3.1. Mo hinh tinh thS natri clorua NaCI 2. Tinh chait chung ciia hop chat ion Tinh the ion rd't ben viing vi lire hiit tinh didn giua cac ion ngugc dd'u trong tinh the ion rd't ldn. Cac hgp chd't ion deu kha rdn, khd bay hoi, khd ndng chay. Thi du : Nhiet do ndng chay cua NaCl la 800 °C, cua MgO la 2800 °C. Cac hgp chd't ion thudng tan nhidu trong nudc. Khi ndng chay va khi hoa tan trong nudc, chiing ddn didn, cdn d trang thai rdn thi khdng ddn didn. BAI TAP 1. Lien ke't hoa hoc trong NaCI dugc hinh thanh la do A. hai hat nhan nguyen tif hut electron rat manh. B. moi nguyen tuf Na va Cl gdp chung 1 electron. C. mdi nguyen tuf dd nhudng hoac thu electron de trd thanh cac ion trai dau hiit nhau. D. Na ^^ Na-' + e ; Cl + e -> C r ; Na'' + Cl" ^ NaCI. Chgn dap an dimg nhat. 2. Mud'i an d the ran la A. cac phan tuf NaCI. B. cac ion Na* va C\'. C. cac tinh the hinh lap phuong, trong dd cac ion Na* va Cl" dugc phan bd luan phien deu dan tren moi dinh. D. cac tinh the hinh lap phuong, trong dd cac ion Na* va Cl" dugc phan bd luan phien deu dan thanh timg phan tuf rieng re. Chgn dap an diing nha't. 3. a) Viet ca'u hinh electron cua cation liti (Li*) va anion oxit (O^-). b) Nhumg dien tich d ion Li* va O^" do dau ma cd ? c) Nguyen tuf khi hie'm nao cd ca'u hinh electron gid'ng Li* va nguyen tuf khi hiem nao cd cau hinh electron gid'ng O^" ? d) Vi sao 1 nguyen tuf oxi ke't hop dugc vdi 2 nguyen tuf liti ? 4. Xac djnh sd proton, ncrtron, electron trong cac nguyen tuf va ion sau : a)^H^;°Ar, ?,^Cr, ,>^* , b)-Ca- , -s - -AP*. 5. So sanh sd electron trong cac cation sau : Na*, Mg^*, AP*. 6. Trong cac hgp chat sau day, chat nao chifa ion da nguyen tuf ? Ke ten cac ion da nguyen tuf dd. a) H3PO4 ; d) K2SO4 ; b) NH4NO3 ; e) NH4CI ; c) KCl ; g) Ca(OH), 2- m • Bi "«i LJ^N K^T CON G HOA TRj • Su hinh thanh lien ke't cpng hoa tri trong phan tir dan chat va hpp chat nhu the nao ? • Su phan cue trong lien ket cpng hoa tri nhu the nao ? • Phan loai cac loai lien ket hoa hoc theo hieu dp am dien. I - s y HiNH THAN H LI^ N K^T CON G HO A TRj 1. Lien ket cgng hoa tri hinh thanh giira cac nguyen tiJr giong nhau. Sir hinh thanh don chat a) Su hinh thdnh phdn tu hidro (Hy) Nguydn tu H (Z = 1) cd cd'u hinh electron la Is', hai nguydn tii H lien kd't vdi nhau bang each mdi nguydn tir H gdp 1 electron tao thanh mdt cap electron chung trong phdn tir H2. Nhu the' trong phdn tir Hj, mdi nguydn tir H cd 2 electron, gid'ng cd'u hinh electron ben viing ciia khf hidm heli : H- + .H —> ("^ ^ ; H : H Mdi chd'm bdn kf hidu nguydn td bieu didn mdt electron d ldp ngoai cung. H : H dugc ggi la ^ong IIUK cin. 11 I, thay hai chd'm bang 1 gaeh, ta cd H - H ggi la coivj ihirc cau lao, Giiia 2 nguydn tir hidro cd 1 cap electron lidn kd't bidu thi bang mdt gaeh (-), dd la lion kci don. b) Su hinh thdnh phdn tu nita (N^) Cd'u hinh electron cua N (Z = 7) ls^2s^2p^, cd 5 electron d ldp ngoai cimg. Trong phdn tir nito Nj, de dat cd'u hinh electron ciia nguyen tir khf hiem gdn nhd't (Ne), mdi nguyen tir nito phai gdp chung 3 electron. •.N. + :N. > V^^^J ' :N::N: ; N = N Cimg iliifc electron Cong thiic cdu tan Hai nguyen tir N lien kd't vdi nhau bdng 3 cap electron lidn ke't bieu thi bdng ba gaeh (=), dd la i 1 i i 1 \<. Lidn ket ba nay ben nen d nhiet do thirdng, khf nito kem hoat ddng hoa hgc. 61 Lien kd't dugc hinh thanh trong phan tir H2, Nj vira trinh bay d trdn la lien kd't cdng hoa tri. 1 It n kcl Cdiic lu),! Ill i,i lien kci (luuv la o non L'iiia hai nmivc n Uf IMML: im.'l lui) •ihicp (. ,ip c I'.'t I!, 'il 1. iiiinc Mdi cap electron chung tao ndn mdt lidn kd't cdng hoa tri. Cac phdn tir Hj, Nj tao ndn tir hai nguydn tir ciia cimg mdt nguydn td (cd do am dien nhu nhau), nen „ ai cLip cicciioii ciiunt; khouc bi hui lech v;.' pin 1 II,:.HI\CII in nao. Do dd, lidn kd't trong cac phdn tir dd khdng bj phdn cue. Dd la : . 11 ! ci cone hoa tl I LlinllL' cUc. 2. Lien ket giua Cik nguven tu khae nhau. Su hinh thanh hgp chat a) Sli hinh thdnh phan tu hidro clorua (HCl) Trong phdn tir hidro clorua, mdi nguydn tir (H va Cl) gdp 1 electron tao thanh 1 cap electron chung de tao nen mdt lien ket cdng hod tri. Do dm dien eua clo la 3,16 ldn hom do dm didn ciia hidro la 2,20 ndn cap electron lidn ket bj lech vd phfa clo, lidn kd't cdng hoa tri nay bj phdn cue. H- + -Cl: > [ H (:)Clj ; H :C1: ; H - Cl Cong thiic electron Cong thitc cd'u tqo Trong cdng thirc electron ciia phan tir cd cue, ngudi ta dat cap electron chung lech ve phia kf hidu ciia nguydn tir cd do am didn ldn hom. Thi du : H :C1 Lidn kd't cdng hoa trj trong dd i ap electron (iuiiiL' hi lech \e plii'j moi ngii\ cn lu dugc ggi la hen kei eong ho;i in eo cue hay hen ket COIIL; lio;i ui pliaii cue. b) Su ldnh thdnh phan tu khi cacbon dioxit (CO.,) (cd cdu tao thdng'^^) : Cd'u hinh electron ciia C (Z = 6) la Is22s22p2 hay (2, 4), nguydn tir cacbon cd 4 electron d ldp ngodi cimg. Cd'u hinh electron cua O (Z = 8) la Is22s22p'^ hay (2, 6), nguydn tif oxi cd 6 electron d ldp ngoai ciing. Trong phdn tir CO^. nguyen tir C d giiia 2 nguydn tir O vd nguyen tir C gdp chung vdi mdi nguydn tir O hai electron, mdi nguydn tir O gdp chung vdi nguydn tir C hai electron tao ra 2 lidn kd't ddi. Ta cd : •6 + 2:0: > (of:) C ^?^j ; :d::C::0; ; 0 = C = 0 Cdng thuc electron Cong thirc cdu tao *'' Phan tii H-,0 va NH, co cau tao goc (xem bai doc them trang 67). Nhu vdy, theo cdng thiic electron, mdi nguydn tir C hay O ddu cd 8 electron d ldp ngodi ciing, dat cd'u hinh ben vumg cua khi hidm. Do dm didn cua oxi (3,44) ldn hon dd dm dien cua C (2,55) ndn cap electron chung lech ve phfa oxi. Lidn kd't giiia nguyen tir oxi va cacbon la phdn cue, nhung phan tir CO2 cd'u tao thang ndn hai lidn kd't ddi phan cue (C = O) tridt tidu nhau, kd't qua la phan tir nay khdng bj phdn cue. 3. Tinh chait cua cac chait co lien ket cpng hoa tri - Cac chd't ma phdn tu chi cd lidn kd't cdng hod trj cd the la chd't rdn nhu dudng, liru huynh, iot... Cd the la ehd't ldng nhu : nudc, aneol... hodc chd't khi nhu khf cacbonic, clo, hidro,... Cac chd't cd cue nhu etanol (rugu etylic), dudng,... tan nhidu trong dung mdi cd cue nhu nudc. Phan ldn cdc chd't khdng cue nhu luu huynh, iot, cac chat hiiu co khdng cue tan trong dung mdi khdng cue nhu benzen, cacbon tetraclorua... Ndi chung, edc chat chi cd lidn kd't cdng hod tri khdng cue khdng ddn didn d mgi trang thai. II - oO AM DI^N VA LI^N K^T HOA HOC 1. Quan he giua lien ket cong hoa trj khong cue, lien ket cong hoa tri CO cue va lien ket ion Trong phdn tir, nd'u cap electron chung d giiia 2 nguydn tir, ta cd lidn kd't edng hod trj khdng cue. Nd'u cap electron chung lech ve mdt phfa ciia mdt nguydn tir thi dd la lidn kd't edng hod trj cd cue. Nd'u cap electron chung chuydn vd mdt nguydn tir, ta se cd lidn ket ion. Nhu vay, lien ket ion cd the dugc coi la trudmg hgp rieng eiia lien ket cdng hod trj. 2. Hieu do am dien va lien ket hoa hoc De danh gia loai lien ket trong phdn tir hgp chat, ngudi ta cd thd dua vao hidu do dm dien. Ngudi ta phdn loai mdt cdch tucmg dd'i loai lidn kd't hod hgc theo quy udc kinh nghiem dua vao thang do dm dien eua Pau-linh nhu sau*' * : Hieu do am dien Loai lien ket tu 0,0 (Jen < 0,4 Lien ket cong hoa tri khong cue iLf 0,4 den < 1,7 Lien ket cpng hoa tri c6 cue - ' Lien ket lon "^ Hieu dp am dien chi cho ta dir dodn ve mat li thuyet loai lien ket hoa hoc trong phan tir, Dir doan nay con phai duac xac minh dp diing din bcri nhifiu phucmg phap thuc nghiem khae. 63 Thi du : Trong NaCl, hieu do dm didn cua Cl va Na la : 3,16 - 0,93 = 2,23. Vdy, lidn kd't giiia Na va Cl la lidn kd't ion. Trong phdn tir HCl, hidu do dm didn eiia Cl va H la : 3,16 - 2,20 = 0,96. Vdy, lidn kd't giiia H va Cl la lidn ke't edng hod trj cd cue. BAI TAP 1. Chgn cau dimg nha't ve lien ke't cgng hoa trj. Lien ket cdng hoa tri la lien ke't A. giifa cac phi kim vdi nhau. B. trong do cap electron chung bj lech ve mdt nguyen tuf. C. dugc hinh thanh do sudung chung electron cua 2 nguyen tuf khae nhau. D. dugc tao nen giiira 2 nguyen tuf bang mgt hay nhieu cap electron chung. 2. Chgn cau dung trong cac cau sau : A. Trong lien ke't cdng hoa tri, cap electron lech ve phia nguyen tuf cd do am dien nhd hdn. B. Lien ke't cdng hoa trj cd cUc dugc tao thanh giiira 2 nguyen tuf cd hieu do am dien tir 0,4 de'n nhd hon 1,7. C. Lien ke't cdng hoa trj khdng cue dugc tao nen tif cac nguyen tuf khae hin nhau ve tinh cha't hoa hgc. D. Hieu do am dien giura 2 nguyen tuf Idn thi phan tuf phan cue ye'u. 3. Do am dien cua mgt nguyen tuf dac trUng cho A. kha nang hut electron cua nguyen tuf dd khi hinh thanh lien ke't hoa hgc. B. kha nang nhudng electron cua nguyen tuf do cho nguyen tuf khae. C. kha nang tham gia phan irng manh hay ye'u cua nguyen tuf dd. D. kha nang nhudng proton cua nguyen tuf dd cho nguyen tuf khae. Chgn dap an dimg. 4. The nao la lien ke't ion, lien ke't cdng hoa tri khdng cue, lien ket cdng hoa trj cd cUc ? Cho thi du minh hoa. 5. Dua vao hieu do am dien cua cac nguyen td, hay cho bie't loai lien ke't trong cac chat sau day : AICI3, CaClg, CaS, AI2S3. (Lay gia tn do am dien ciia cac nguyen to d bang 6, trang 45.) 6. Viet cdng thdc electron va cdng thifc cau tao cua cac phan tuf sau : CI2, CH4, C2H4, C2H2, NHg. 7. X, A, Z la nhijmg nguyen td cd sd dOn vj dien tfch hat nhan la 9, 19, 8. a) Viet ca'u hinh electron nguyen tuf cuia cac nguyen td dd. b) Du doan Hen ke't hoa hgc cd the cd giCra cac cap X va A, A va Z, X va Z. 64 Bdi doc them § 1. SU XEN PHU CAC OBITAN NGUYEN TU SU LAI HOA CAC OBITAN NGUYEN TU 1 - SLJ XLN PHU CAC OBITAN NGUYEN TU Theo quan diem hien dai, khi 2 nnLiyen tit lai gan nhan, nen \ac snat lim ihay elctiroi i () LjiCia J r.'^ii\' n In do tang len ihi ( o lien kei hoa hot ne'u no bang khong thi khong cd lien ket hoa hoc. Oe giai thfch su tao thanh lien ket hoa hoc noi tren, nguoi ta dua ra khai niem sir xen phil cac obitan nguyen tir. Co hai kieu xen phu : - Xen phn lmc : Su xen phii xay ra tren true noi giua hai hat nhan nguyen tir. Su xen phu nay tao ra hen kei o (xu h rnai, Thi du : Su xen phii true giua 2 obitan s ciia 2 nguyen tir hidro tao lien ket a trong phan tir H2. .#s^; + 1s Is Sir xen phu cua 2 obitan 1s cua hai nguyen tCr hidro - Xen |)hLi lien : Su xen phii thuc hien a hai ben true noi giua hai hat nhan nguyen tir. Su xen phil nay tao ra It n kei - 1 pi <. Thi du : Xen phii ben trong phan tir CjH^. / , H "fi h" c = c Su xen phil true giua hai nguyen tir lan hon xen phu ben nen lien ket CT ben hon lien ket rt. 5-HH10-C/A 65 II - s u LAI HO,\ CAC ()B1T,\\ NCiLA EN TU' Trong thuc te, cac nguyen tir lien ke't cong hoa trj vai nhau trong phan tir khong chi nam tren mpt duong thSng ma con phan bo tren mat phang va trong khong gian. De giai thich duac lien ket trong cac phan tir do, Pau-linh la nguai dau tien dua ra khai niem su lai hoa cac obitan nguyen tir. SLI lai In )a ttit nhi lan n;_;Li\en lu l,i sn in hop i lie in 1,'ini m()l so ohilan IV^LIS r n In in )iig niol nL;u\en In (te IIIHH Iniv^ .n ohiKiii kn ho j ',^ioiv4 nhaii nliLing rlinh hnoiv.; kh,i' iih,ui Irong khon.; -ian Cac obitan tham gia lai hoa phai cd nang lugng khong khae nhau nhieu. Thi du 1 : Lai hoa thing sp trong phan tir BeHj. 180° ?^v. lAOs lai hoa vdi lAOp 2A0 lai hoa sp Thi du 2 : Lai hoa sp^ trong phan tir BFj. 120° Phan til BeHj lAOs lai hoa vdi 2A0p 3A0 lai hoa sp^ Phan tCr BF3 Thi du 3 : Lai hoa sp^ trong phan tir CH^. 109°28 lAOs lai hoa vdi 3AOp 4AO lai troa sp'' Ptian tu CH4 66 5-HH10-C/B V'ler ( hon dang lai hoa nao de giai thi< h su lien kei noni:' plian In ln\ IIIIKK \ .n. ( ,111 1IU( hmh hot tlu;' n-hiem < na phan In Thi du, phan tir metan CH^ co cS'u true tu dien, ta chon 4 AO lai hoa sp^ ciia nguyen tir cacbon de giai thi'ch su xen phii true ciia chiing voi 4AOs cuia 4 nguyen tir H tao ra 4 lien ke't CT trong phan tir metan voi goc lien ket 109°28'. Con trong phan tir BeFj co cau true tam giac deu, ta lai phai chon lai hoa sp^ de giai thich goc lien ke't trong phan tir do la 120° ... ( Jliilan lai ho.i 1 hi \en phi.i liui de Uio lien ket n. § 2. SU T.AO THANH PHAN TU H3O, NH, (cd cau tao ^dc) 1 - Pll.-XN TUNUOC (H.O) Cong thirc electron ''o' H H Cong thirc cau lao H 105° H Hinh 3.2. Md hinh rdng (a) va dac (b) cua phan tCtnUdc Ca'u hinh electron cua nguyen tur H la 1s \ ciia nguyen tir O la 1s^2s22p''. Khi tao thanh phan tir HjO , mdi nguyen tir H gop chung 1 electron vai nguyen tir O va nguyen tir O gop chung 1 electron vai mdi nguyen tir H de tao ra hai lien ket cong hoa trj O-H , goc thuc nghiem la 105°. Op am dien ciia O (3,44) Ion hon dp am dien cua H (2,20) nen lien ke't O- H bj phan cue. Ke't qua la phan tir Hj O bj phan cue. 4b 11 - Pll.AN TU,\M{3N1,\C (NH.) Cong thirc electron H •• H H Hinh 3.3. Md hinh rdng (a) va dac (b) cua phan td amoniac Cau hinh electron ciia nguyen tir N la 1s^2s^2p^, ciia nguyen tir H la 1s^ Khi hinh thanh phan tir NH3, nguyen tir N gop chung vai mdi nguyen tir H 1 electron va moi nguyen tir H gop chung vai nguyen tir N 1 electron tao ra 3 lien ke't cpng hoa trj N-H , goc thuc nghiem la 107°. Op am dien ciia N (3,04) lan han dp am dien ciia H (2,20) nen lien ket N - H bj phan cue. Ket qua la phan tir NH3 bj phan cue. Phan Ur eo cur hav khong r o citt khong nhung phu thLux wv) hieu do am dien cua cac ngu\en tu ma con phu thuc'ic vao goc lien ket trong phan tu do, Khi khong can noi den ca'u tao khong gian ciia phan tir, ta co the viet cong thuc cau tao ciia H^O va NH3 tren mat phang dan gian nhu sau : H-O- H H-N- H 1 H m TINH TH^ NGUYEN TLT vA TINH TH^ PHAN TU • The nao la tinh the nguyen tir, tinh the phan tir ? • Ti'nh chat chung ciia tinh the nguyen tir, tinh the phan tir. I - TINH TH^ NGUYEN TLf 1. Tinh the nguyen tiJr Tinh the nguyen tir ca'u tao tir nhirng nguyen tir duge sdp xe'p mdt each deu dan, theo mdt trat tu nha't djnh trong khdng gian tao thanh mdt mang tinh the. O eae diem nut eiia mang tinh the la nhtimg nguyen tir lien ket vdi nhau bang cac lien kd't cdng hoa trj. Kim cuong, mdt dang thii hinh ciia cacbon, thude loai tinh the nguyen tir. Nguyen tir cacbon cd 4 electron ngoai ciing. Trong tinh the kim cuomg, mdi nguyen tir cacbon lien ke't vdi 4 nguyen tir cacbon lan can gan nha't bang 4 cap electron chung, dd la 4 lien ke't edng hoa trj. Cae nguyen tir cacbon nay nam tren 4 dinh eua mdt tti" dien ddu (hinh 3.4). Hinh 3.4. Md hinh cau triic tinh the kim cuang a) Su sSp xep tit dien cua bdn nguyen tCt C xung quanh nguyen tit C trung tam d kim cuang b) Tinh the kim aiang 2. Tinh chat chung ciia tinh the nguyen tir Luc lien ket cdng hoa trj trong tinh the nguyen tir rat ldn. Vi vay, tinh the nguyen tir ben viimg, rat ciimg, nhiet do ndng chay va nhiet do sdi kha eao. Kim cucmg ed do ciing ldm nha't so vdi cac tinh the da bie't nen duge quy udc cd dd ciimg la 10 dom vj. Dd la dom vi de' so sanh do ciimg ciia cae chat. 69 II - TINH THi PHAN TL/ Tinh the phan tu Tinh the phan tir ca'u tao tiJf nhiimg phan tir dugc sap xep mdt each deu dan, theo mdt trat tir nha't dinh trong khdng gian, tao thanh mdt mang tinh the. O cac diem niit cua mang tinh the la nhtrng phan tir lien ket vdi nhau bang lue tuomg tae yeu gitra cac phan tir. Phan ldn eae chat hiru co, cac dem chat phi kim d nhiet do thap deu ket tinh thanh mang ludi tinh the phan tir (phan tir ed the gom mdt nguyen tir nhu eae khf hie'm, hoac nhidu nguyen tir nhu cae halogen, Oj, N2, H2, H2O, HjS, COj...). Thi du, tinh the iot (Ij) la tinh the phan tu (hinh 3.5). 2. Tinh chat chung ciia tinh the phan tu *^^ ^ r •n* ^ Phan tif I, Hinh 3.5. Md hinh tinh the phan tCtcCia iot Trong tinh the phan tu, cae phan tir van tdn tai nhu nhirng dom vj doe lap va hiit nhau bang luc tucmg tac yeu giiia cac phan tir. Vi vay, tinh the phan tir dd ndng chay, dd bay hoi. Ngay d nhidt do thudmg, mdt phan tinh the nhu naphtalen (bang phidn) va iot da bj pha huy, eae phan tir tach rdi khdi mang tinh the va khue'eh tan vao khdng khi lam eho ta dd nhan ra mui ciia chung. Cac tinh the phan tir khdng phan cue dd hoa ttm trong eae dung mdi khdng phan cue nhu benzen, toluen, cacbon tetraclorua,... BAI TAP 1. Tim cau sai trong cac cau sau day : A. Kim cuong la mdt dang thii hinh ciia cacbon, thudc loai tinh the nguyen tuf. B. Trong mang tinh the nguyen tuf, cac nguyen tuf dugc phan bd luan phien deu dSn theo mpt trat tu nha't dinh. C. Luc lien ket giiira cac nguyen tuf trong tinh the nguyen tuf la lien ke't ye'u. D. Tinh the nguyen tuf ben viimg, rat cifng, nhiet dp ndng chay va nhiet dp sdi kha cao. 2. Tim cau sai trong cac cau sau day : A. Nudc da thudc loai tinh the phan tuf. B. Trong tinh the phan tuf, luc lien ke't giiira cac phan tuf la lien ke't cgng hoa tri. C. Trong tinh the phan tuf, lUc lien ke't giQa cac phan tuf la lien ke't ye'u. D. Tinh the iot la tinh the phan tuf. 70 3. Hay ke ten cac loai tinh the da hgc va tinh chat chung cua timg loai. 4. a) Hay dua ra mgt sd thi du chat cd mang tinh the nguyen tuf, chat cd mang tinh the phan tur. b) So sanh nhiet dp ndng chay cua hai loai tinh the ndi tren. Giai thich. 5. Vi sao cac hgp chat ion cd nhiet dp ndng chay cao ? 6. Hay neu lien ket hoa hoc chu ye'u trong 3 loai mang tinh the da bie't. Tu lieu TINH THf PHAN TL/ CUA NL/OC DA Tai sao nu(r( long tin linh diing va nang, nuoc c\:\ thi i ung va nhe hrrn lUKrc long ? t^ien do (luo( giai thu h nhu -.an : Trong nuac long ca< phan ILI IUKH ( hnven dong mot (>i( h de dang va (rgan nhan, Nlurng trong tinh the phan tir lUKrc d,^. ( M phan tu nu(r( sap xep IIH'O mot thu II ; nhat dinh, ca( phan ILI niiCK ct c ar h \a nhau h x = -3 . Trong HNO2 : (+1) + x + 2.(-2) = 0 ^ x = +3. Trong NO3 : x + 3.(-2) = -1 ^ x = +5. Cdch riei so o.xi liod : Sd oxi hoa dugc vid't bang ehii sd thudmg, da'u dat phfa -3+1 trudc va duge dat d trdn kf hidu nguyen td. Thf du : NH^ BAI TAP 1. So oxi hoa cuia nito trong NH^, NO2 va HNO3 lan lugt la A. +5, -3, +3. C. +3, -3, +5. B. -3, +3, +5. D. +3, +5, -3. Chgn dap an dimg. 2. Sd oxi hoa ciia Mn, Fe trong Fe^*, S trong SO3, P trong P0^~ lan lugt la A. 0, +3, +6, +5. C. +3, +5, 0, +6. B. 0, +3, +5, +6. D. +5, +6, +3, 0. Chgn dap an dung. 3. Hay cho biet dien hoa tr| cuia cac nguyen td trong cac hgp chat sau day : CsCI, Na20, BaO, BaClj, AI2O3. 4. Hay xac dinh cdng hoa trj cua cac nguyen td trong cac hgp chat sau day : H2O, CH4, HCl, NH3. 5. Xac dinh so oxi hoa cuia cac nguyen to trong cac phan tuf va ion sau : CO2, H2O, SO3, NH3, NO, NO2, Na^ Cu2^ Fe^-^, Fe^\ A|3^ 6. Viet cdng thifc phan tuf ciia nhiing chat, trong dd S lan lugt cd sd oxi hoa -2, 0, +4, +6. 7. Xac dinh sd oxi hoa cuia cac nguyen td trong cac hgp chat, don chat va ion sau : a) H2S, S, H2SO3, H2SO4. b) HCl, HCIO, NaCI02, HCIO3, HCIO4. c) Mn, MnCl2, Mn02, KMn04. d) Mn0:,S02-,NH+, ' a 4 4 74 • Bai LUYEN TAP : LIEN KET HOA HOC • Ciing cd cac kien thuc ve cac loai lien ket hoa hpe chi'nh de van dung giai thich su hinh thanh mpt so loai phan tir. Dac diem ca'u true va dac diem lien ke't ciia 3 loai tinh the. • Ren luyen kl nang xac djnh hoa tri va sd oxi hoa cua nguyen to trong don chat va hap chat. A - KIEN THUC CAN NAM VUNG Bang 9. So sanh lien ket ion va lien ket cpng hoa tri Loai Mdn kd't Ojnh nghTa Lien kdt ion Lidn ket ion la lien k^t duoc hinh thanh bdi luc hilt tinh dien giiia cac ion mang dien tich trai dau. Lidn kd't cong hoa trj Khong cue C6 ci/c Lien ket cpng hoa trj la lien ket duoc tao nen giura hai nguyen tuf bang mot hay nhieu cdp electron chung. B^n chat ciia lidn kiit Hieu dd am dien Ddc tinh Electron chuyen tif nguyen tif nay sang nguyen tif kia. >1,7 Ben. Doi electron chung khong lech ve nguyen tif n&o. 0^<0, 4 Doi electron chung lech ve nguyen tif nao CO dp am dien I6n hon. 0,4-^<1,7 Ben. Bang 10. So sanh tinh the ion, tinh the nguyen tu, tinh the phan tu Tinh thd ion Tinh the nguyen tiif Tinh thd phdn tiir Khai nidm Life lien kd't D|c tinh Cac cation va anion duoc phan bo luan phien deu dein d cac diem nut cua mang tinh the ion. Cac ion mang dien tich trai dau hut nhau bang lUc hut tinh dien. Luc nay ldn. Ben, kh^ ran, kho bay hoi, kho nong chay O cac diem nut cua mang tinh the nguyen tuf la nhiing nguyen tuf. Cac nguyen tif lien ket vdi nhau bang luc lien ket cpng hoa trj. Luc nay rat ldn. Ben, kha cOng, khd ndng chay, khd bay hd. u cac diem nut cua mang tinh the phan tuf la nhOrng phan tif. Cac phan tir lien ket vdi nhau bang life hut giura cac phan tii, ye'u hon nhieu luc hut tmh dien giCfa cac ion va luc lien ke't cpng hoa tri. Khdng ben, dS ndng chay, de bay hoi. 75 B - BAI TAP 1. a) Viet phuong trinh bieu diln sU hinh thanh cac ion sau day tir cac nguyen tir tuong dng : Na -^ Na"- ; Cl -^ Cl" Mg ^ Mg2-^ ; S ^ S^- Al ^ A|3* ; O ^ 02- b) Viet ca'u hinh electron cuia cac nguyen tuf va cac ion. Nhan xet ve ca'u hinh electron ldp ngoai ciing cua cac ion dugc tao thanh. 2. Trinh bay su gid'ng nhau va khae nhau cua 3 loai lien ke't: Lien ke't ion, lien ke't cgng hoa tri khdng cue va lien ket cdng hoa trj cd cUc. 3. Cho day oxit sau day : Na20, MgO, AI2O3, SiOj, PjOg, SO3, CI2O7. DUa vao gia tri hieu dp am dien ciia 2 nguyen tuf trong phan tuf, hay xac dinh loai lien ket trong tirng phan tif oxit (tra gia tn do am dien d bang 6, trang 45). 4. a) Dua vao gia tn do am dien (F : 3,98 ; O : 3,44 ; Cl : 3,16 ; N : 3,04 ), hay xet xem tinh phi kim thay ddi nhuthe nao trong day nguyen td sau : F, O, Cl, N. b) Viet cdng thufc ca'u tao ciia cac phan tuf sau day : N2, CH^, H2O, NH3. Xet xem phan tif nao cd lien ke't cdng hoa tri khdng phan cue, lien ke't cdng hoa trj phan cue manh nha't. 5. Mdt nguyen tuf cd ca'u hinh electron 1s22s22p''. a) Xac dinh vi tri cuia nguyen td dd trong bang tuan hoan, suy ra cdng thifc phan tuf hgp chat khi vdi hidro. b) Viet cdng thifc electron va cdng thu'c ca'u tao cuia phan tuf dd. 6. a) Lay thi du ve tinh the ion, tinh the nguyen tuf, tinh the phan tuf. b) So sanh nhiet dp ndng chay cua cac loai tinh the dd. Giai thich. c) Tinh the nao din dien dugc d trang thai ran ? Tinh the nao di n dien dugc khi ndng chay va khi hoa tan trong nudc ? 7. Xac djnh dien hoa tri cua cac nguyen td nhdm VIA, VIIA trong cac hgp chat vdi cac nguyen to nhdm IA. 8. a) Dua vao vi tri cua cac nguyen td trong bang tuan hoan, hay neu rd trong cac nguyen td sau day nhiimg nguyen to nao cd ciing cdng hoa trj trong cdng thifc hoa hgc cac oxit cao nha't: Si, P, Cl, S, C, N, Se, Br b) NhOmg nguyen td nao sau day cd ciing cdng hoa trj trong cdng thufc hoa hgc cua cac hgp chat khi vdi hidro ? P, S, F, Si, Cl, N, As, Te. 9. Xac dinh sd oxi hoa ciia Mn, Cr, Cl, P, N, S, C, Br: a) Trong phan tif: KMnO^, Na2Cr207, KCIO3, H3PO4. b) Trong ion : NO" ; SO f ; CO^" ; Br" ; Nl-T^. 76 Chuang \P\ um m)A - \mi& • Sir oxi hoa, sir khu. chit oxi hoa, chat khu va phan ling oxi hoa - khu la gi ? ^ Diu hieu nao giup ta nhan biet phan ung oxi hoa - khu ? •^ Mudn lap phuang trinh hoa hoc cua phan ung oxi hoa - khu ta phai lam thi nao ? ^ Dua vao sd oxi hoa ta cd the chia cac phan ihig vd ca thanh miy loai ? Phan Ung oxi hoa - khd xay ra khi ddt chay nhien lieu, tao ra nang luang day con tau bay vao vu tru 77 »!i PHAN LTNG OXI HOA - KHLT • Bai UL Su oxi hoa, su khir, chat oxi hoa, chat khir va phan ung oxi hoa - khir la gi ? Cach lap phuang trinh hoa hpe ciia phan iing oxi hoa - khir. I - DINH NGHlA Thi du T Khi dd't chay magie trong khdng khf, xay ra su oxi hoa magie. Phan ling duge bieu didn bang phuomg trinh hoa hgc : 0 0 +2- 2 2Mg + O2 —> 2MgO (1) Ta xac djnh sd oxi hoa cua magie trude va sau phan iing. Tnrdc phan iing, magie ed sd oxi hoa 0, sau phan iing ed so oxi hoa +2. O phan ling nay, Mg nhudng electron : 0 +2 Mg —> Mg + 2e Qua trinh Mg nhudng electron la qua tiinh oxi hoa Mg (stt oxi hoa Mg). Thi du 2. Su khir CuO bang Hj xay ra theo phan iing : +2-2 0 0 +1-2 CuO + Hj —> Cu + H2O (2) Ta xae djnh so oxi hoa cua dong tnrdc va sau phan iing. Trudc phan iing, ddng cd sd oxi hoa +2 (trong CuO), sau phan ting ed so oxi hoa 0. +2 O phan ling nay, Cu thu electron : +2 0 Cu + 2e —> Cu +i +2 +2 Qua trinh Cu thu electron ggi la qua trinh khur Cu (su khii Cu). 78