5.74. Dap an diing la Ạ
Gang, thep la hop kim Fe - C d^ trong khdng khi ^m bi Sn mon dien hoạ
5.75. Dap an dung la B.
Kim loai tinh khiet (triif kim loai nhom l A va IIA) rat kho bi an mon a nhiet
d6 thucfng khi de ngoai khdng khị
200
iw' .76. Dap an dung la B.
Trong dung dich FeCl3 da xay ra phan ling : Fê"*" + Fe -> 2 Fê"*"
Fê-^/Fê^ Fê*/Fe
Trong dung dich CUCI2 da xay ra phan iJng : Cu^^ + Fe -> Cu + Fê"*^
Cu^'-ZCu Fê-'/Fe
5.77. Dap an diing la B.
Phuang trinh (Fe -> Fê^ + 2e) bieu thi su oxi hoa Fẹ
5.78. Dap an dung la B.
Dira vao day the dien hoa dé sap xep.
5.79. Dap an dung la C.
Cation kim loai c6 tinh oxi hoa cang manh thi bi khuf dien a catot cang sdrm.
Do do CO thir tir C.
5.80. Ket luan khong diing la A .
Tir phuang trinh ion : Cu + 2 Ag"^ -> Cu^"^ + 2Ag
Ta c6: E ° , > E ° Ag"^ c6 tinh oxi hoa khir manh han Cu^"^.
A g V A g Cu^-'/Cu
5.81. Dap an diing la D.
Dung bot lim huynh cha vao ch6 c6 thuy ngan, luu huynh se khir thuy ngan thanh mu6'i, tranh duae hai thuy ngan boe len (Hg + S HgS).
5.82. Dap an dung la C.
Ta da biet : E ° , > E ° > E ° , vi AgNOj du nen tát ea
A g V A g FéVFê^ Fê^Fe ^ ^
Fe bi oxi hoa thanh Fê^. Trong dung dich chi eo Fe(N03)3va
AgN03 dụ
I 5.83. Dap an diing la B. I - x •«
Khi cho CuCl2 vao, ion Cú^"^ bam vao thanh sat, tao thanh nhung pin nho
(Cu^"^ la cue duong) 6iy nhanh qu<i iiinh an mon dien hoạ
5.84. Ket luan sai la Ạ
Dang oxi hoa ciia cap oxh/kh c6 E° 16n han c6 tinh oxi hoa manh han dang oxi hoa ciia cap oxh/kh c6 E° nho hcfn. Ngucfc lai, dang khir cap c6 E° nho
C O tinh khii manh han dang khir ciia cap eo E° lom han.
5.85. Dap so diing la B.
Ap dung dinh luat BTKL :
'T>K.loai+ n i H 2 S 0 4 = rnmuói +
^ rrimutfj = 1.04 + 0,03 .98 - 0,03.2 = 3,92 gam.
5.86. Dap so dung la C.
Phuang trinh phan ling :
Zn + 2AgN03 ^ Zn(N03)2 + 2 A g 4 (1) T h e o ( l ) :
Cii 2 mol AgN03 phan ling lam thanh kem tang : 2 .108 - 65 = 151 gam 0,1 .0,1 mol AgN03 ohan iJng lam thanh kem tang : m gam.
151.0,1.0,1
-> m = ^ = 0,755 gam.
5.87. Dap s6' diing la D.
Phuomg trinh phan ling :
Fe + CUSO4 ^ FeS04 +Cui (1)
T h e o ( l ) :
Cii 1 mol CUSO4 phan ling lam thanh Fe tang : 64 - 56 = 8 gam
Vay X mol CUSO4 phan fing lam thanh kem tang : 0,8 gam.
- > X = 0,1 mol ^ C M ( CUSO4 ) = — = 0,5 M .
202
,88. Dap s6' diing la Ạ
ẠỊt Ap dung c6ng thirc dinh luat Faraday : m =
nF , m.n.F 1,92.2.96500
-> I = = — — = 3,0Ạ
Ạt 64.1930 fjiv:^
89. Dap so dung la B. v qi,{v v .
Phuang trinh phan ling dien phan : f
dpđ
C u ( N 0 3) 2 + H 2 O ^ C u + 0, 5 O 2 + 2HNO3
Khi bat dau c6 khf ( ) thoat ra d catot, tire la Cu(N03) 2 da bi dien phan het. Ap dung c6ng thirc dinh luat Faraday tinh dugc kh6'i luang Cu thoat ra
a catot: ẠỊt 64.9,65.(40.60) ^ ^„ ẠỊt 64.9,65.(40.60) ^ ^„ m = = = 7,68 gam. nF 96500.2 ^ -90. Dap so dung la D. dpđ
Phuang trinh phan iitig dien phan : X C I 2 > X + C I 2
K i m loai X thoat ra b catot c6 nguyen til kh6'i A :
, m.n.F 1,92.2.96500 , A = = = 64 (Cu). A = = = 64 (Cu).
Ịt 3.1930
KIM LOni KI€M -
Chiicfng 6
KIM LOni KI€M THO - NHOM
6.1. Dap an diing la B. 6.2. Dap an diing la C. 6.2. Dap an diing la C. 6.3. Dap an diing la Ạ 6.4. Dap an diing la D. 6.5. Dap an diing la Ạ 6.6. Dap so diing la C. Phuong trinh phan ling :
CaCOj +2HC1 -> CaClj + C 0 2 t + HjO (1)
Theo (1) : ncoj = ncaco, = ] ^ =
"NaOH = 0.5 0,4 = 0,2 mol
~ * "^NaOH > "002 • ^9 duoc háp thu vao dung dich NaOH du6i dang mu6'i cacbonat.
BaCl2 + C O i " ^ BaC03i + 2 C r (2) Theo (2) : ngaco, = i c O z = 0,15.
meaCOj = 0,15 .197 = 29,55 gam.
6.7. Dap s6' diing la B.
Cac Phuong trinh phan ling :
X2CO3 + 2HC1 ^ 2XC1 + CO2 t + H2O (1)
YCO3 + 2HC1 -> YCI2 + CO2 T + H2O (2)
4 48
Theo ( 1 , 2 ) : ncô = D H ^ O = ^ = 0'^ "^ô- nHci = 2 . nco2 = 0,4 mol.
204
Theo dinh luM BTKL :
20 + 36,5 .0,4 = m + 44 .0,2 + 18 .0,2 m = 22,2 gam.
6.8. Dap s6' diing la C.
BaC03 + 2HC1 -> BaCl2 + CO2 t + H2O
3 94
Ta c6: neaCO, = ^ = 0,02 mol ; nnci = 0,2 mol
•i
(1)
(1)
(2) Theo (1) : D^ hoa tan 0,02 mol BaCOj diing het 0,04 mol HCl. Theo (1) : D^ hoa tan 0,02 mol BaCOj diing het 0,04 mol HCl.
"HCldu = 0 , 2 - 0 , 0 4 = 0,16 mol.
HCl + NaOH NaCl + HjO (2)
iiNaOH = "HCldu = 0,16 mol -» VNaOH = = 0,32 l i t = 320 ml.
6.9. Dap so diing la D.
Cac phuong trinh phan ling :
AICI3 + 3NaOH ^ A1(0H)3 4 + 3NaCl • 0,1 mol 0,3 mol 0,1 mol
A l ( 0 H ) 3 i + NaOHdu -> N a A l O j i +2H2O
0,02 mol 0,02 mol
S6' mol A1(0H)3 i thu duoc la : 0,1 - 0,02 = 0,08 mol.
mAl(0H)3 = 0,08 .78 = 6,24 gam.
6.10. Dap an dung la Ạ
Cac phuong trinh phan ling :
NaA102 + CO2 + H2O ^ A1(0H)3 i + NaHC03
NaAlOj + H2O + HCl dii ^ A1(0H)3 i + NaCl 3NaA102 + AICI3 +6H2O ^ 4 A l ( O H ) 3 i + 3NaCl
6.11. Dap an diing la D.
6.12. Dap an diing la C.
6.13. Dap an diing la C.
6.14. Dap an diing la B.
6.15. Phuang trinh sai la C.
6.16. Nhan xet khdng diing la B.
6.17. Dap an sai la D.
6.18. Phucfng phap diing la C.
6.19. Dap an diing la Ạ Phan trng xay ra : Phan trng xay ra :
2NaOH + CăHC03)2 -> CaC03>l + Na2C03 + 2 H 2 O
6.20. Dap an dung la B.
Cac phuang trinh phan ling :
2Na + 2 H 2 O -> 2NaOH + H21
CUCI2 + 2 N a O H - > C u( 0 H ) 2 i + 2NaCl
1.21. Dap an diing la D. Phuang trinh phan" ling : Phuang trinh phan" ling :
2NaOH + 2 NO2 -> NaN03 + NaN02 + H2O
M u 6 i NaN02 bi thuy phan, cho moi trudng baza, pH >7.
6.22. Dap an diing la C.
Cho 3 chat bOt vao 3 6ng nghiem dung dung dich N a O H . - (!) ong nghiem nao bot khong tan la bpt M g .
- d ong nghi6m nao bot tan, c6 k h i thoat ra la bot A l .