phân loại và phương pháp giải nhanh bài tập hóa học vô cơ 12

• -•««>•' « CU THANH TOAN; (I I & PhUdng phdp gial nhanh BAI TAP loral NHAXUATBAN Cdc em hoc sinh Idp 12 than md'n! nam vChig kiS'n thiic va c6 the dat ket qua cao nha't trong cac ki thi, cac em hoc sinh c^n ren luyfin giai nhanh cac dang bai tap thucmg xuyfen, lifin tuc trong qua trinh hoc tap ciia minh. Di cac em c6 th6m tai Vitu tu ren luyfin cac kl nang giai bai tap, chupg t6i xin tran trong gioi thidu h6 sach: "Phdn loai vd phuong phdp giai nhanh bai tap hod hoc 12". ' •• PMn V6 CO g6m 5 chuong: ^ Chuong 5: Dai cuong \i kim loai Chuong 6: Kim loai k\6m - Kim loai ki^m th6 nh6m Chuong 7: Crom - Sat - D6ng Chiromg 8: Nhan bie't mot s6' chat v6 co va chu^n d6 dung djch Chuong 9: Hoa hoc vdri va'n d^ kinh i6, xa h6i va m6i trucmg Trong m6i chuong duoc trinh bay: A. Ly thuyd't co ban B. Phuong phap giai cac dang bai tap M6i bai tap trong sach duoc tac gia chon loc kl cang, la sir k6't tinh ciia kifi'n thiic CO tinh chat t6ng hop kd't hop v6i kinh nghidm nhilu nam luy6n thi. Cac bai tap nay co gia tri rat cao v^ n6i dung, co d6 tin cay rat 16n trong ki^m tra, danh gia. Cac bai tap duoc n6u ra trong tap sach d^u duoc giai chi tifi't, d^y dii, d6 hi^u va theo cac phuong phap giai nhanh. Tac gia xin b^y to long bid't on sau sSc su gop y chan thanh ciia cac ban d6ng nghifip va cac em hoc sinh. Chuc cac em dat kd't qua cao trong hoc tap. ' Tac gia Mia sach Khang Vi^t xin tran trgng giai thi$u tai Quy dgc gid vd xin idng nghe mgi y kim dong gop, decuon sack ngdy cdng hay han, botch han. Thu xin giti ve: Cty TNHH Mpt Thanh Vien - Djch Van hoa Khang Vi$t. 71, Dinh Tien Hoang, P. Dakao, Quan 1, TP. HCM Tel: (08) 39115694 - 39111969 - 39111968 - 39105797 - Fax: (08) 39110880 Ho|c Email: khangvietbookstore@yahoo.com.vn Cty TNHH MTV DVVH Khang YTel ChirongS. DAI Clfdll^G KIM MAI I. CAU TAO CUA KIM LOAI 1. Cau tao nguyen tiir: Nguyen tir ciia hSu hd't cac kim loai co s6' electron b Idp ngoai cung it (1, 2, 3 e). 2. Cau tao tinh the: Trong tinh th^ kim loai, nguydn tir va ion kim loai nlm a nhiJng niit ciia mang tinh th6', cac electron hoa tri chuyen dong tu do trong mang tinh the. 3. Lien ket kim loai: La lien ket duoc hinh thanh giOa cac qguySn ttr va ion kim loai trong mang tinh the do sir tham gia ciia cac electron tu do. II. TINH CHAT CUA KIM LOAI 1. Tinh chat vat ly chung Cac kim loai deu dSn didn, dSn nhiet, deo, co anh kim la do cac electron tu do trong kim loai gay ra. 2. Tinh chat vat ly rieng M6t !6' tinh chat vat ly nhu kh6'i luong riSng, nhiet d6 nong chay, tinh ciifng phu thu6c vao do b^n ciia lien ket kim loai, nguySn tir khdi, ki^u mang tinh th^, ciia kim loai 3. Tinh that hoa hoc chung cua kim loai. Cac kim loai deu CO tinh khir: M > M"" + ne Nguyt n nhan: Cac electron hoa trj ciia nguydn tir kim loai lien k6't yd'u vdi hat nhan nguydn tii, do do cac kim loai co kha nang nhuong electron de tao thanh ion duong. a. Tac dung v&i phi kim Hdu hift cac kim loai khir duoc phi kim thanh ion am. Thf du: 4A1 +30, —^ 2A1A Hg + S > HgS : . . h. Tac dung vdi axit * D6'i y&i dung dich HCl, H:S04 loang: Cac kiin loai dung trudc H trong day hoat d6ng hod hoc (day dien hoa) khir duoc ion (H3O*) ciia cac axit nay thanh H2: M+ nH* > M"" + -H,t * D6'i v5i H2SO4 dac, nong; HNO3: nau ha cac kim loai (triT Au, Pt) khii duoc N va- S trong cac axit nay xu6ng s<3 oxi hoa thap hon. Thi du: 3Cu + 8HNO,(l) > 3Cu(NO,)2 + 2NO + 4H,0 2Fe + 6H3S04(d) '" > Fe2(S04)3 + SSO, + 6H3O c. Tac dung vdi H2O - Cac kim loai c6 tinh khir manh nhir kim loai kiem, kim loai kidm tho (Ca, Sr, Ba, truofc Mg trong day dien hoa) khir H^O d6 dang 6 nhiet do thircmg. Thi du: 2Na + 2H.O > 2NaOH + H.T - Mot s6' kim loai khac (nhu Mg, Zn, Fe, ) khir duoc hoi nuoc d nhiet d6 cao: Mg + H^O.h, —^ MgO + H, 3Fe + 4H.O —^ Fe304 + 4H: d. Tac dung vai dung dich niuoi cua kim loai Kim loai manh hon (khong tac dung v6'i H^O) day duoc kim loai y€u hon ra khoi dung djch mu6'i. Thi du: Fe + CuSO^Cdd) > FeSO, + Cui Fe + Cu-" > Fe-" + Cu III. DAY DIEN HOA CUA KIM LOAI 1. Cap oxi hoa - khurcua kim loai Dang oxi hoa (M"*) va dang khu (M) ciia ciing m6t kim loai tao nen m6t cap oxi hoa - khu (M"7 M), giOa chung c6 m6'i quan hd: M"" +ne ( > M 2. Pin dien hoa. - Pin d'ltn hoa la thiet bi trong do nang lugng ciia phan ling oxi hoa - khir (hoa nang) chuyen thanh dien nang. - Pin dien hoa tao bdi hai cap oxi hoa - khu, trong do: • O cue am (anot): Xay ra su oxi hoa chat khir. • 6 cue duong (catot): Xay ra sir khu chat oxi hoa. - Sua't dien dong ciia pin dien hoa: La hieu ciia the didn cue duong (E,+)) v6i th6' dien cue am (£,.,): E(pi,„ = - E,-, > 0 (luon diromg) E° pi„) = EV) - EV, > 0 (sua't dien dong chuan) E,pi„), E°p|,„ phu thuoc vao ban chat ciia kim loai lam dien cue, n6ng d6 dung i dich va nhiet do. 5. The dien circ chuan ciia kim loai - Dien cue hidro chudn : Pt (H,, 1 atm)/H" (IM): H, < > 2W +2e Quyudrc: E^H'/H^ = 0,00 V. - The' dien cue chu£n cua kim loai cdn do duoc cha'p nhan bang sua't difen dOng ciia pin tao bcri dien cue hidro chudn va diSn cue chudn cua kim loai cSn do. t — C (p,„) — (Neu M durng sau H trong day dien hoa). po „+ po M /M — ^ (Dill) (pill) H2+/H2 -E (Neu M diing truoc H trong day dien hoa). 4. Quy tac anpha (a ) 1 Day didn hoa ciia kim loai cho phep du doan chieu eua phan ling giCra hai cap oxi hoa - khir theo quy tac a. Phan ling giOa hai cap oxi hoa - khir xay ra theo chieu chat oxi hoa manh hon se oxi hoa chat khir manh hon sinh ra chat oxi hoa yeu hon va chat khu yeu hon: [oxh|„,„h + [kh] ,„,„h > [oxh]j4„ + [kh] IV. SlTBIEN PHAN - Sir dien phan la qua trinh oxi hoa - khijf xay ra 0 be mat cac didn cue khi c6 dong dien mot chi6u di qua chat dien li nong chay hoac dung dich chat dien li. - Phan ling hoa hoc or cac dien cUc trong binh dien phan: * 6 catot (cue -): Xay ra sU khir: M"" + ne hoac 2H,0 + 2e M 20H" + H. V: 1" * d anot (cue +): Xay ra sU oxi hoa: X" hoac 2H2O X + me —> 4H' + O, + 4e - Neu anot (cue +) kh6ng tro thi anot bj an mon (tan ddn): A >A"" + ae - Tinh khoi luong cac chat thoat ra 6 didn cue: A.I.t m = n.F Trong do m: Khoi lugng chat thu dugc 6 dien cue, ti'nh bang gam. A: Khoi lugng mol cua chat thu dugc 6 dien cue. n: 56' electron ma nguyen tu hoac ion da nhan. I: Cuong do dong dien (A). ,. . r t: Thoi gian dien phan (s). F: Hang so Faraday (F = 96500 C/ mol). - Tinh s6' mol electron trao d6i: n. trao ddi = It/ F (mol) Phdn locii va pluMni^ phc'ip f-idi BT H6a hoc 12 -Cu Thanh Toan V. Sir AN MON KIM LOAI 1. Su an mon hoa hoc va su an mon dien hoa i -Giong nhau: D^u c6 ban chat la phan ung oxi hoa - khir. -Khdc nhau: * Trong an mon hoa hoc khdng hinh thanh dong dien. * Trong an mon dien hoa c6 hinh thanh dong electron (cac electron dirac di chuyen thanh dong, tir cue am d6n cue duong => tao pin difin hoa). 2. Cac dieu kien xay ra an mon dien hoa hoc - Cac difin cue phai khae nhau ban chat. - Cac didn cue phai tid'p xiic true tiep hoac gian tiS'p vdi nhau qua day dSn. - Cac dien cue cung tiep xuc vdri dung dich chat dien li. Chu y; Thie'u 1 trong 3 dieu kifen tren se khdng xay ra an mon dien hoa hoc, ma se xay ra an mon hoa hoc. 3. Chong an mon kim loai - Bi6n phap bao \t be mat: scm, trang, ma, b6i diu m5, phii chat deo, \tn hi mat kim loai. - Bidn phap bao vt ditn hoa: Diing kim loai c6 tfnh khir manh hom d^ bio vfi (anot hi sinh). VI. PHUONG PHAP DIEU CHE KIM LOAI 1. Phuofng phap thuy luyen (phuong phap udt) * Ca sff: Dung nhOng dung dich thich hop, nhu dung djch H2SO4, NaOH, NaCN, de hoa tan kim loai hoac hop chat ciia kim loai va tach ra khoi phan khong tan CO trong quang. Sau do cac ion kim loai trong dung djch duoc khir bang kim loai c6 tinh khir manh hem. * Phant vi dp dung: Duoc diing de' dieu che nhOng kim loai c6 tinh khir yS'u nhu Cu, Hg, Au, * Thi du: Di6u che bac tir quang chira bac sunfua: Ag.S + 4NaCN > 2Na[Ag(CN)2] + Na,S 2Na[Ag(CN)2] + Zn > 2Ag + Na.[Zn(CN)4] 2. Phuong phap nhiet luyen * Ca sa: Khir nhUng ion kim loai trong cac hop chat thucmg la exit kim loai o nhiet do cao bang cac chat khu manh nhu C, CO, H, hoac Al, kim loai ki^m, kim loai kiem th6. * Phqm vi dp dung: Uhg dung r6ng rai trong cong nghiep de di^u che' nhffng kim loai c6 d6 hoat dong trung binh nhuZn, Fe, Sn, Pb, Cr, V6i kim loai kern hoat dong nhu Ag, Hg thi chi cin dot chay quang cung da thu duoc kim loai ma khdng phai khiJr bang cac tac nhan khac. HgS + O. > Hg + SO, " " ' Ag,S + O, —^ 2Ag + SO, *Thidu: Fe^Oj + 3CO 2Fe + 3CO, CrA + 2A1 '" > 2Cr + AUOj ZnO + C Zn + CO Chu v; Khi CO nong chi khir duoc cac ion kim loai trong cac oxit diing sau kem trong day dien hoa, thi du FeO, PbO, CuO, 3. Phuomg phap dien phan * Casa: Dung dong didn m6t chieu de khir cac ion kim loai. r, * Phqm vi dp dung: Co the diSu che duoc hdu het cac kim loai. - Dieu che' kim loai c6 tinh khir manh nhu Li, Na, K, Al, bang each dien phan nhung hop chat (mud'i, baza, oxit) nong chay ciia chiing. - Dieu che' kim loai c6 tinh khir trung binh va kim loai c6 tinh khir yeu nhu Zn, Cu, bang each dien phan dung djch mu6'i cua chiing. *r/(/c/M 2NaCl > 2Na+ Q, 2AI3O3 ^n"^.^""i" )4AI +30, 2CUSO4 + 2H,0 2Cu + 2H,S04 + O^ ^ B. PHUCM(5 PHAP GJAO C-Ac 'D:^Na BAO T^P Dang 1: Bai tap kim loai tac dung vol dung djch muo'i, axit va phi kim 1. Kh6'i luong la kem giam khi ngam la kem vao dung dich (gia thie't khi kim loai thoat ra bam he't vao la kem, kem chi bi oxi hoa boi ion kim loai) A. CdCl,. B. AgNOj. C. PbCNOj),. D. CUSO4. Hu&ng ddn gidi Cac PTPU" xay ra: „ •,, i Zn +CdCl, > Cdi +Zna, ^'f- x X (mol) «>•:"' ' Am = 112x - 65x > 0 => kh(5i luong la Zn tang. ^ ' ;; Zn + PbCNO,), > Pbl + ZnCNOj), ; X X (mol) , , , Am = 207x - 65x > 0 kh6'i luong la Zn tang. ' ^ :^ ' Zn + 2AgN03 > 2Agi + Zn(N03), " ' X 2x • ^ , Am=:2.108x-65x>0=>kh6'iluonglaZntang. . Phan loai va phirati}> phi'ip i^iai BT Hoa hoc 12 - Cu Thanh Toan Zn + CUSO4 > Cu 4^ + ZnS04 X x(mol) Am = 64x - 65x < 0 => kh6'i lirong la kem giam. Dap an dung la D. 2. Cho a gam h6n hop bot cac kim loai Ni va Cu vao dung djch AgNO, dir, khuS'y kl m6t thofi gian cho den khi phan ling k^'t thiic, thu duoc 54 gam kim loai. Mat khac, cung cho a gam h6n hop bot cac kim loai tren vao dung djch CUSO4 du, khua'y kT cho den khi phan ling ket thuc, thu duoc kim loai c6 khoi luong bang (a + 0,5) gam. Gia trj cua a la A. 13,5 g. B. 15,5 g. C. 18,6 g. D. 20,4 g. Hu&ng dan gidi Goi X, y \&n luot la s6' mol Ni, Cu trong h6n hgfp. Ta c6: a = 59x + 64y * PTPU" xay ra khi cho Ni, Cu + AgNO^Cdd, du): Ni + 2AgNO., > 2Ag>l +Ni(N03). X 2x Cu + 2AgN0, > 2Agl +Cu(N03)2 y 2y 54 Tac6: 2x + 2y = =>x + y = 0,25 (1) 108 * PTPU" xay ra khi cho Ni, Cu + CuS04(dd, dir): Ni + CUSO4 > Cui + NiS04 X X „: Cu + CuS04-^ y Taco: 64x + 64y = a + 0,5 = 59x + 64y + 0,5 ' =:>5x = 0,5 =>x = 0,l (2) Tir(l,2)^x = 0,l; y = 0,15. Vay a = 59. 0,1 + 64.0,15 = 15,5 Dap an diing la B. 3. Hai la kim loai ciing chat, c6 khoi luong bang nhau: Mot duoc ngam vao dung dich Cd(N0,)2; mot duoc ngam vao dung djch PbCNO,),. Khi phan ling, kim loai diu bj oxi hoa thanh ion kim loai 2+. Sau mot thai gian, la'y cac la kim loai ra khoi dung djch thi tha'y kh6'i luong la kim loai duoc ngam trong mu6'i cadimi tang them 0,47%; con khoi luong la kim loai kia tang them 1,42%. Gia thiet rang, trong hai phan ung tren khoi luong kim loai tham gia phan ufng la nhu nhau. Kim loai da diing la A.Zn. B.Fe. C. Cu. D. Mg. Hu&ng dan gidi Kl hifiu kim loai do la M, s6' mol M phan ume la x: khA'i lirnmfr M h;in rtaH la m tn\ PTPlT: M + Cd(N03), > Cdi +M(N03)2 X X (ii2-M).x 0,47 ' Taco: M + PbCNOj), > Pbi + M(N03)2 (207-M).x^M2 'y'^' [2) 207-M 1,42 ^ 2 Dap an dung la A. Uy(2):(l)taduoc: = 112-M 0,47 =>207-M =336-3M=>2M= 129=^M«65(Zn) 4. Nhiing mot thanh sdt nang 100 gam vao 100 ml dung djch h6n hop g6m Cu(N03)2 0,2M va AgNOj 0,2M. Sau mot thdi gian lay thanh kim loai ra, rua sach lam kh6 can duoc 101,72 gam (gia thiet cac kim loai tao thanh deu bam het vao thanh sdt). Khoi luong sat da phan ung la A. 1,40 gam. B. 0,84 gam. C. 2,16 gam. D. 1,72 gam. Hu&ng dan gidi Theo bai ra: ncu(N03)2 = 0,1. 0,2 = 0,02 (mol); "AgNO., =0,1. 0,2 = 0,02 (mol). Truofctien: Fe + 2AgN03 > 2Ag i + Fe(N03)2 ' Khi 0,02 mol AgNOj phan ling het thl khoi luong thanh kim loai se tang: '' 0,02. 108 - 0,01. 56 = 1,6 (gam) < 1,72 (gam). => AgNOj phan iJng het, va mot phSn Cu(N03)2 da phan iJng: Fe + Cu(N03)2 > Cu i + Fe(N03)2 Khi 1 mol Fe > 1 mol Cu => kh6'i luong tang 8 gam Khi khoi luong tang 1,72 - 1,6 = 0,12g => so mol Fe da phan ung la =0,015 (mol) < 0,02. 8 Vay tong khoi luong Fe da phan irng la mp, = (0,01 + 0,015). 56 = 1,40 (gam) Dap an diing la A. 5. De khir ion Cu"* trong dung djch CUSO4 c6 the diing kim loai A. Ba. B. K. C. Fe. D. Na. Huong dan gidi De khCr ion Cu-* trong dung djch CUSO4 c6 the dung kim loai Fe: Phdn loai va phuang phdp gidi BT Hoa hoc 12 - CM TIU. ! an Fe + CUSO4 > Cu + FeS04 Dap an dung la C. 6. khu ion Fe'* trong dung dich thanh ion Fe'* c6 ths' diing m6t lugng du A. kim loai Cu. B. kim loai Ba. C. kim loai Ag. D. kim loai Mg. Hu&ng ddn gidi D6' khii ion Fe'* trong dung dich thanh ion Fe"* c6 the dung m6t luong dir kim loai Cu: Cu + 2Fe'* > Cu"* + 2Fe-* Dap an dung la A. 7. Cho day cac kim loai: Cu, Ni, Zn, Mg, Ba, Ag. S6' kim loai trong day phan ting ducfc vdi dung djch FeCl, la A. 5. B.4. C. 3. D.6. Hu&ng ddn gidi PTHH: 1) Cu + 2FeCl3 ^ CUCI2 + 2FeCl2 2) Ni + 2FeCl3 ^ NiCl2 + 2FeCl2 3) 3Zn + 2FeCl3 3ZnCl2 + 2Fe 4) 3Mg + 2FeCl3 ^ 3MgCl2 + 2Fe 5) 3Ba + 6H2O + 2FeCl3 ^ 3BaCl2 + 2Fe(OH)3 + 3H2 Dap an dung la A. 8. Cho h6n hop gom Fe va Mg vao dung dich AgN03, khi cac phan ling xay ra hoan toan thu duoc dung dich X (g6m hai muoi) va chat rSn Y (gom hai kim loai). Hai mu6'i trong X la A. Mg(N03)2va Fe(N03)2. B. Fe(N03)3va Mg(N03)2 C. Fe(N03)3 va AgNOj D. AgN03 va Mg(N03)2. Huong ddn gidi - Y gom hai kim loai => Hai kim loai la Ag, Fe du - X gom hai mu6'i => Hai mu6'i la MgCNOj)! va FeCNOj), (Vi Fe con du nen AgNO, het, khong the sinh ra FeCNO,),) Dap an dung la A. 9. Cho 2,8 gam b6t sat vao 200 ml dung dich gdm AgNO3 0,lM va CU(NO3)2 0,5M; khi cac phan ling xay ra hoan toan thu duoc m gam cha't ran X. Gia trj cua m la A-4,08. B.3,20. C. 4,48. D. 4,72. Huong ddn gidi Theo bai ra: np, =0,05mol; n^gNOj =0,02mol ncu(N03)2 =0,lmol Thii tu phan iJng: Fe + 2AgN03 ^ Fe(N03)2 + 2Ag 4- 7;; 0,01 ^0,02 0,02 , ,< • Fe + Cu(N03)2 ->Cu4 + Fe(N03)2 ; > I (0,05-0,01)-^ 0,04 ^0,04 ' Vay m - m^g + = 0,02.108 + 0,04.64 = 4,72 g Dap an dung la D. 10. Cho m gam b6t sat vao dung dich h6n hcfp gom 0,15 mol CuS04va 0,2 mol HCl. Sau khi cac phan ling xay ra hoan toan, thu duoc 0,725m gam h6n hop kim loai. Gia tri cua m la A. 16,0. B. 18,0. C. 16,8. D. 11,2. Huong ddn gidi VI sau phan ling thu duoc h6n hop kim loai (Cu, Fe du) => Fe du => CUSO4 va HCl h6i. Fe + CUSO4 ->FeS04+Cui 0,15 <-0,15 ^ 0,15 Fe + 2HC1 -> FeCl2 + H2 t 0,1 <- 0,2 Theo bai ra: mp^ ,d^) + m^u = 0,725m => m - 56. (0,15 + 0,1) + 0,15.64 = 0,725m =>0,275m =4,4 ^m = 16,0 Dap an dung la A. 11. Hoa tan 5,4 gam bot Al vao 150 ml dung djch A chiia Fe(N03)3 IM va Cu(N03)2 IM. Ket thuc phan feg thu duoc m gam ran. Gia tri ciia m la A. 10,95 B. 13,20 C. 13,80 D. 15,20 Huong ddn gidi Theobaira: n^, = 5,4/27 = 0,2(mol) . nFe(N03)3 -0,15.1 =0,15(mol);nc„(NO3)2 =0,15.1 =0,15(mol) Thirtutrong day dian hoa: Al^+ /A^Fe^* /Fe;Cu^^ /Cu;Fe^^ /Fe^^ V Dovay,thiirtircacPTHH: " Al + 3Fe^^^Al^^+3Fe2+ 0,05 -> 0,15-^ 0,15(mol) 2A1 + 3Cu2+ 3Cui+2Al^+ 0,1 <-0,15 0,15(mol) 11 Phan loai vaphifcfn^phiip fiidi />/ //oti hoc 12 -Cii ' h.i / )/; 2A1 + SFe^"" ^ 3Fe i +2A\^^ 0,05 0,075 ^ 0,075(mol) Vay m = mcu+ mp, =0,15.64+ 0,075.56 = 13,80(g) »ap an dung la C. 12. Cho a mol bot kem vao dung djch c6 hoa tan b mol Fe(NO,),. Tim dieu kien lien he giOa a va b de sau khi ket thiic phan ung khong c6 kim loai. A. a > 2b B. b > 3a C. b > 2a D. b = 2a/3 Huong ddn gidi Di sau phan ung khong c6 kim loai thi luomg Zn (phan ung het) chi khu Fe-^^-^Fe^^ Zn + 2Fe(N0,), -> Zn(N0,)2 + 2Fe(N03)2 Ban ddu: a b (mol) Phan ung: a 2a (mol) Do do b > 2a thi Zn phan ling het (bj tan het) va Fe'^^ Fe^^ (dd) Dap an diing la C. 13. Cho h6n hop kim loiii Mg, Zn, Fe vao dung dich chiia AgNO, va CuCNO,),. Sau khi phan ling xay ra hoiin toan thu duoc dung dich X g6m 3 muoi va chat rSn Y gom ba kim loai. Ba mudi trong X la A. Mg(N03)3, Fe(N03),, AgNO., B. Mg(N03)„ Zn(NO.,)„ Cu(N03), C. Mg(N03),, Zn(N03),, Fe(NO,,), D. Mg(NO.,):, Zn(NO,,)., Fe(NO,). Hu&ng ddn gidi Thu" tir cac kim loai nay trong day dien hoa: Mg2+ /Mg;Zn2^ /Zn; Fe^^ /FeiCu^^ /Cu;(Fe-'^ /Fe2+);Ag^ /Ag => Kha nang phan ling ciia cac kim loai: Mg > Zn > Fe > Cu > Ag Do do 3 kim loai sau phan ling la: Ag;Cu;Fe . Vi Fe con du nen: + Mg, Zn phan ling het => c6 mu6'i Mg(N03)2 '^"(^^^.Oi + Mu6'i Cu(N03)2;AgNO, het => khong c6 cac mu6'iCu(N03)2 ,AgN03 trong dung dich sau phan umg. + Kh6ng tao ra muoi Fe(N03)^ ma tao ra mu6'i Fe(NO,)2 ' vay 3 mu6'i trong X la Mg(N03)2 ;Zn(N03)2 ;Fe(N03)2 • '' ' ' Dap an dung la D. Cty TNHH MTV DVVH Khang Viet 14. Cho 29,8 gam h6n hcrp bot gom Zn va Fe vao 600ml dung djch CUSO4 0,5M. Sau khi cac phan ling xay ra hoan toan, thu dugc dung dich X va 30,4 gam h6n hop kim loai. Ph^n tram vd khdi lucmg ciia Fe trong h6n hop ban ddu la A. 43,63%' B. 56,37% C. 64,42% D. 37,58% Huong ddn gidi ,. Theobaira: ncu,so4 =0'60,5 = 0,3(mol) Vi khdi luong hdn hop kim loai sau phan ling lodi hon khdi luong hdn hop tru6c phan ling (30,4g > 29,8g) => Fe da phan ling mot phdn. Do do, CUSO4 da phan ling het, hdn hop kim loai sau phan ling gdm Cu va Fe dir. ,. ^ Goi X, y, z Idn lirot la sd mol Zn, Fe phan ling, Fe con du. PTHH: Zn + CUSO4 -> ZnS04 + Cu i X -> X -> X Fe + CUSO4 -> FeS04 + Cu i y ^ y -> y Taco: x + y=0,3 65x + 56.(y + z) = 29,8 56z + 64.(x + y) = 30,4 Giai ra ta dugc: x =0,2;y = 0,l;z = 0,2 56.(y + z).100% 56.(0,1 + 0,2). 100% vay: %mp, =—^- '- = — — = 56,37% 29,8 29,8 Dap an dung la B. 15. Cho a mol Al vao dung dich chiia b mol Fe"* va c mol Cvr*. Ket thiic phan ling thu duoc dung djch chiia 2 loai ion kim loai. Ket lufln nao sau day la diing? , 2b 2(b + c) A. —<a<—^ - 3 3 2(b + c) 3 3 C.^<a< 3 3 3 2(b + c) Hu&ng ddn gidi Vi dung dich thu dugc chiia 2 ion kim loai (Al'* sinh ra va Fe""^ con du) => Cu-' het (Cu-* phan ling trudc Fe*); Al het (vi Fe"* con du). PTPlT: 2A1 + 3Cu2^ > 3Cu I +2A1^+ j,.,,. , (D , hu>'A — <— c(mol) 2A1 + 3Fe^^ > 3Fe i + 2A1 3+ (2) ( 2c 1 3 20 a a 3 2 3 Phdii locii vu pliif<yiii> plu'ip i^idi BT Hoa hoc 12 — Cu Thanh Toan - Vi Al phan utig vijfa du hoac con dir b phan utig (1) n6n: ^2c a > — 3 - Vi Fe-* con dir (phan irng 2) nfen: (I) a 2c ^ <b 3a ^ 3a \b + c) => c<b=> — <b + c =J'a<-— 2 2 3 Tir(I),(II) 2c 2(b + c) (11) Dap an dung la C. 3 3 16. Cho m gam h6n hop bot X gom Fe, Cu vao 600ml dung djch AgNO, IM. Sau khi ket thiic phan iJng thu duoc dung djch Y g6m 3 muoi (kh6ng chiia AgNOj) CO khdi luong giam 50 gam so v6i ban dSu. Gia tri ciJa m la A. 64,8 B. 14,8 C. 17,6 D. 114,8 >; Hu&ng ddn gidi Theobaira: nAgN03 =0>6(mol) - Vi dung djch sau phan ling thu duoc 3 muoi => Fe, Cu phan ung het - Trong dung djch sau phan irng khdng c6 AgNOj => AgNOj da phan ting het. So 66 phan ling: Fe,Cu + AgNOj ^ Fe (NO3 \u (NO3 \(NO3 )3 + Ag i Ta c6: m + m ddAgN03 ""^Ag"^ """"^ddsau Dap an diing la B. ^ m + mddAgN03 =0,6.108 + (m,dAgNO3 "^^j =>m =0,6.108-50 = 14,8(gam) CM v: Cac PTPLT xay ra: Fe + 2AgN03 -> Fe(N03)2 + ^ Cu + 2AgN03 ^ Cu(N03 \ 2Ag I Fe(N03)2 + AgN03 -> Fe(N03)3 + ^8 ^ 17. Ngam h6n hop 3 kirn loai Fe, Cu, Ag trong luong du dung djch cha't X, khua'y ky cho den khi phan iJng ket thiic thi cha't rSn thu duoc chi c6 Ag va c6 khdi lugng bang khdi luong ciJa no trong hdn hop dSu. Vay X la A.CUSO4 B.Fe(N03)3 C.HC1 D. AgNOj Huong ddn gidi X phai la Fe(N03)3, that vay: Fe + 2Fe(N03)3 ^ 3Fe(N03)2 Cu + 2Fe(N03)3 ^ 2Fe(N03), + CuCNOj), Cty TNHH MTV DVVH Khans ^'4* Con lai Ag khdng phan ung, luong con lai dung bang luong ban ddu. Dap an dung la B. 18. Cho m gam bot sat tac dung vdi 175 gam dung djch AgN03 34%, sau phan ling thu duoc dung djch X chi chiia 2 mudi sat va 4,5m gam cha't ran. Ndng d6 ciJa Fe(N03)3 trong dung dich X la A. 7,60% B. 12,36% C. 8,31% D.9,81% . Hu&ng ddn gidi Theo bai ra: n AgN03 = "J^^ = 0,35(mol) Vi dung djch X khdng con AgNOj => AgNO, het => n^g - nAgN03 = 0,35(mol)=>mAg = 0,35.108 = 37,8 (gam) => 37,8 = 4,5m =:>m = 8,4(gam)=>np^ = 8,4/56 = 0,15(mol) Goi X, y \k\t la sd mol Fe(N03)2 va Fe(N03)3 Ta c6: 2x + 3y = 0,35 (bao toan electron) X + y = 0,15 (bao toan nguyen td sat) Giai ra ta duoc: x = 0,1; y = 0,05 vay C,,,o ) ="'"^•^^^•'"'^^-8,31% DapandanglaC. • ^ Fe(N03)3 175 + 8,4-37,8 Chu V. Khdi luong phdn dung dicll sau phan ling: •"dd = ""ddAgNOj + "Ipe - "lAg4. 19. Cho m, gam Al vao 100ml dung dich gdm Cu(N03)2 0,3M va AgNO, 0,3M. Sau khi cac phan ung xay ra hoan toan thi thu duoc mj gam chat ran X. Neu cho mj gam X tac dung vdi luong du dung djch HCl thi thu duoc 0,336 lit khi (o dktc). Gia trj ciJa m, va m^ Mn luot la A.0,54va5,16 B. I,08va5,43 C.8,10va5,43 D. I,08va5,16 Hu&ng ddn gidi Theo bai ra: ncu(N03)2 " ^'' -^'^ " 0,03mol; "AgNOj = 0,1.0,3 = 0,03mol;nH2 =0,336/22,4 = 0,015mol Ag •iiMi'rtu So dd phan ung xay ra: Al ^l^ff^ > \u > H2 t PTHH: Al Al + 3AgN03 -> 3Agi +A1(N03)3 0,01 <- 0,03 -> 0,03 2A1 + 3Cu(N03)2-^ 3Cui + 2Al(N03)3 0,02 <- 0,03 0,03 2A1 + 6HCI -> 2AICI3 + 3H2 t 0,01 <- 0,015 Vay:m, =(0,01 + 0,02 + 0,0l).27 = l,08(g) „ ^ , m2 =mcu+mAj, =0,03.64+0,03.108=5,16(g) Dap an diing la D. 20. Day nao sau day chi gom cac chat vira tac dung duoc vdi dung djch HCl, vira tac dung duofc vorj dung djch AgNO,? A. Hg,Na,Ca B. Al, Fe, CuO C. Fe, Ni, Sn D. Zn, Cu, Mg. Huong ddn gidi Day gom cac chat vira tac dung v6i dung djch HCl, vira tac dung v6i dung dich AgNO, la Fe, Ni, Sn. Fe + 2HC1 FeCl2+H2 Fe + 2AgN03 Fe(N03)2+2Ag Ni + 2HC1 ^ NiCl2+H2 Ni + 2AgN03 -> Ni(N03)2+2Ag Sn + 2HC1 -> SnCl2+H2 Sn + 2AgN03 ^ Sn(N03)2 + 2Ag Dap an diing la C. 21. Nhung mot la kim loai M (chi c6 hoa trj hai trong hop chat) c6 khoi lirong 50 gam vao 200ml dung dich AgNO, IM cho den khi phan iJng xay ra hoan toan. Loc dung djch, dem c6 can thu duoc 18,8 gam muoi khan. Kim loai M la A. Mg B. Cu C. Fe D. Zn Huong ddn gidi Theobai ra: n^^j^^^ =0,2.1 =0,2 (mol) M + 2AgN03 ^M(N03)2 + ^Ag 4- 0,1 <-0,2 ^ 0,1 Gia sir M la kim loai Zn (kim loai c6 phan tiJr khoi Idn nha't => c6 s6' mol nho nhat) thi n^, = 50/65 = 0,77mol >0,1 => Kim loai M con du, AgNOj phan linghet. TheoPTHH=>n^NO^)^=0,l(mol) =>MM(NO3)2 = ' 8,8/0,1 = 188 MM = 188 - 62.2 = 64(Cu) Vay M la kim loai Cu. Dap an diing la B. 22. Cho h6n hop gom 0,02 mol Fe vii 0,01 mol Cu vao dung djch chiia 0,065 mol AgNO,, sau cac phan ung hoan toan thu duoc 200 ml dung djch X. N6ng do cua Fe(N03), trong dung djch.X la A.0,05M '£pa;075r^», C. 0,025M D.O.IOM Cty TNHH MTV~DWH Khang Viet Hu&ng ddn gidi Trat tir day didn hoa: Fe'V Fe; Cu'V Cu ; Fe'7 Fe'^; AgV Ag nen trinh tir cac phan ling xay ra nhu sau: Fe + 2AgNO, -> Fe(N03)2 + 2Agi ' 0,02 0,04 -> 0,02 (mol) '' Cu + 2AgN03 Cu(N03)2 + 2Ag i 0,01 -> 0,02 S6' mol AgNO., con lai 0,065 - (0,04 + 0,02) = 0,005 (mol) Fe(N03), + AgNO, -> Fe(N03)3 + Agi 0,02 0,005 (banddu) 0,005 <- 0,005 ^ 0,005 (mol) vay nong do Fe(N03)3 trong dung djch X: CFe(N03), =^ = 0'025 (M) Dap an dung la C. 23. Hoa tan h6n hop chiJa dong thai 0,15 mol m6i kim loai Fe va Cu trong 675ml dung djch AgNOjlM, khoi luong chat rSn thu duoc khi ke't thiic phan dng la A. 75,3 B.64,8 C. 70,2 D. 72,9 Hu&ng ddn gidi Theo bai ra: nAgN03 =0,675(mol) Thiitutrong day dien hoa: Fe^+/Fe; Cu^^/Cu; Fe^+/Fe^+; Ag+/Ag Fe + 2AgN03 -> Fe(N03)2 + 2Ag^ 0,15^0,075 -)• 0,15 ^ 0,3 Cu + 2AgN03 ^Cu(N03)2+2Agi 0,15^0,3 / -> 0,3 Fe(N03)2 +AgN03 >• Agi + Fe(N03)3 0,075 <- 0,075 -> 0,075 vay m,i„ = m^gi = 0,675. 108 = 72,9 (gam) Dap an dung la D. 24. Cho 1,76 gam h6n hop bot X gom Cu, Fe c6 ti 16 mol tuong ling la 1: 2 vao 100ml dung djch AgNO, IM, khua'y kl d^ cac phan urng xay ra hoan toan. Khd'i luong Ag thu duoc la A. 6,48 gam B. 8,56 gam C. 10,8 gam D. 8,64 gam. Hu&ng ddn gidi Theo bai ra: nAgN03 =^'1 ('"°') Goi X la s6' mol Cu => s6' mol Fe 1^ 2x. fH'J VI^N Tl'.MH «iNH THl.'ANJ ——— ^—— :L Ta c6: 64x + 56. 2x = 1,76 => x = 0,01 (mol) Vi thiJ tu trong day di6n hoa: Fe-'/Fe; Cu'VCu; Fe-*/Fe'"; AgVAg Nen thii tix phan ung xay ra: Fe +2Ag" Fe-" +2Ag>l 0,02^0,04-^0,02^0,04 ' '\h Cu + 2Ag"Cu-" + 2Agi , 0,01 ->0,02 0,02 Fe-" + Ag" ^ Fe'* +Agi 0,02 -> 0,02 ^ 0,02 => n + = 0,04 + 0,02 + 0,02 = 0,08 < 0,1 => Ag" con du = n^ + (Pu) = 0,08 (mol) => m^g = 0,08. 108 = 8,64 (gam) Dap an dung la D. 25. Hoa tan 5,4 gam b6t Al vao 150 ml dung dich h6n hop Fe(N03)3 IM va Cu(N03)2 JM- Sau khi phan ihig xay ra hoan loan thu duoc m (gam) chat ran. " Gia tri cua m la * A. 13,80. B. 10,95. C. 15,20. D. 13,20. Hu&ng dan gidi Theobaira: n^, =0,2mol; np^ =0,15mol "Cu(N03)2 Thu- tu cac PTHH xay ra: Al + 3Fe (NO, \ Al (NO, \ 3Fe (NO, \ 0,05<-0,15 ^ 0,15 2Al+3Cu(N03)2->3Cui+2Al(N03)3 0,1 <-0,15 -^0,15 2A1 + 3Fe(N03)2 ^ 3Fe i +2A1(N03)3 0,05-> 0,075 -> 0,075 Vay m= 0,15.64+ 0,075.56 = 13,80(g) Dap an dung la A. 26. Hoa tan 1,57 gam h6n hop b6t kim loai gom Al, Zn vao 100 ml dung djch h6n hop AgNO, 0,1M va Cu(N03)2 0,3M. Sau khi phan ling xay ra hoan toan thu diroc chat ran X va dung dich Y chi chiJa hai mudi. Ngam X trong dung djch H2SO4 loang kh6ng tha'y c6 khi thoat ra. Cho dung dich NH3 dir vao Y thi thu dugc bao nhieu gam ket tua? A. 1,96 gam B. 2,74 gam C. 1,56 gam D. 0,78 gam Hu&ng dan gidi [ Theobaira: n^gNOj =0,1.0,1 =0,01 mol Cty TNHH MTV DVVH Khang Via ncu(NO3)2-0'10'3 = 0,03mol So d6 phan ling: ' Al,Zn + AgN03,Cu(N03)2 ^ X^^^ + 2 mudi (dd) Suy ra: ' ' "' '^^ ^ , • • + Hai mudi la Al(N03)3,Zn(N03)2 => AgN03,Cu(N03)2 he't + Chat ran X khdng tac dung vdi H2SO4 loang => X chura Ag va Cu (Al, Zn deu het) Do do, Al va Zn phan ung vijfa dii vori AgNO, va Cu(N03)2 , ;j . Qua trinh cho - nhan electron: Al Al-''+ + 3e X -> X -> 3x(mol) Zn -> Zn^^ + 2e y -> y ^ 2y (mol) Ag"^ + le -> Agi 0,01 ->0,01 Cu^+ + 2e ^ Cu i 0,03 -> 0,06 =^3x + 3y = 0,01+0,06 =0,07 (l) > Mat khac: 27x + 65y = 1,57 (2) Tir(l,2) ^x=0,01;y = 0,02 Al-^^+3NH3+3H20->Al(OH)3 i+3NH; Zn^^ + 6NH3 + 3H20->[Zn(NH3)^](OH)2+2NH; Khdi luong ket tiia thu dirge: m i= 78x = 78.0,01 = 0,78(g) Dap an dung la D. 27. Cho m gam bdt sat vao dung dich chiia 0,2 mol AgNOj va 0,1 mol Cu(N03)2, khua'y deu den khi cac phan ling xay ra hoan toan thu dugc 19,44 gam chat ran. Gia tri ciia m la ^^ A. 5,6 B.5,04 C.3,36 D. 8,4 Hu&ngddngidi ^ ,1 i Gia siJr AgN03 phan lifng het thi tao ra 0,2 mol Ag m^g = 0,2.108 = 21,6(g) > 19,44(g) [...]... loai va pinfcng phcip fjicii BT Hoa hoc 12 -Cii Thanh Toari 3 Hoa tan 13,68 gam muoi MSO4 vao nuac duoc dung dich X Dien phan X (voi dien circ tro, cuonig do dong dien khong doi) trong thofi gian t giay, dirge y gam k i m loai M duy nha't a catot va 0,035 mol khi a anot Con neu thbi gian dien phan la 2t giay thi t6ng so mol khi thu dugc a ca hai dien cue la 0 ,124 5 mol Gia trj cua y la • A 4,480 B... dung djch sau khi ngirng dien phan: m —>M4+H2S04 0,07 + 0,502 ^ => 0,1 ( m o l ) (1) T n.F 0,1 0,2 ( m o l ) 0 ,12. 1.96500 I =4320(giay) 2,68 = l,2(gic0 V i t, = 1,2 (gior) < 2(gi6r) => c6 (2) xay ra Thdi gian o x... - l g ( K r 2 j ^ 2 5 Dien phan (dien circ bang dong dien c6 9650 giay dien phan A 1,792 lit Dap an diing la C tro) dung dich X chiia 0,2 mol CUSO4 va 0 ,12 mol NaCl cuong do 2A The ti'ch khf (dktc) thoat ra 0 anot sau la B 2,240 lit C 1,344 lit D 2, 912 lit Huong dan gicii Cac qua trinh xay ra a anot (+): Tnroc tien: 2 C r -2e H,0-2e +4NaCN,a,, > 2Na|Ag(CN),l + Na,S Zn + 2Na[Ag(CN),|,,„ > 2Ag + Na,... 200 va 6,5 C 400 va 13,0 D 200 va 13,0 >CK t X '•unrmA ,1^' j^j^, C dung dich H:S04 dac, nong va Zn D dung dich HCl dac va Zn Huong dan gidi Cac PTPU'xay ra: Vay can dung them dung dich NaCN va Zn 0 ,12- >0 ,12^ 0,06 (mol) Sau do: Cty TNHH MTV DVVH Khan^ ViJt Todii B A l v a M g C Na va Fe D Mg va Zn Huong dan gidi Cac kim loai Cu, Ag c6 the dieu che bang phuong phap dien phan dung dich: Dap an diing la . -•««>•' « CU THANH TOAN; (I I & PhUdng phdp gial nhanh BAI TAP loral NHAXUATBAN Cdc em hoc sinh Idp 12 than md'n! nam vChig kiS'n thiic va c6 the dat ket qua. t6i xin tran trong gioi thidu h6 sach: "Phdn loai vd phuong phdp giai nhanh bai tap hod hoc 12& quot;. ' •• PMn V6 CO g6m 5 chuong: ^ Chuong 5: Dai cuong i kim loai. 'y'^' [2) 207-M 1,42 ^ 2 Dap an dung la A. Uy(2):(l)taduoc: = 112- M 0,47 =>207-M =336-3M=>2M= 129 =^M«65(Zn) 4. Nhiing mot thanh sdt nang 100 gam vao 100 ml dung djch h6n