1 .
>1 >1 <1 >1
CH3COONa + HCl = CH3COOH + NaCl
, .
CH3COO- + Na + + H+ + Cl - = CH3COOH + Na + + Cl -
CH3COO- + H+ = CH3COOH ( )
(CH3COOH) <1 = 1*107
(HCl)>1 - = 1,85*10-5
: . <1; (CH3COOH) <1.
2 .
1. NH4OH + - ( ( ), )
2. NH4OH + - + NH4Cl ( )
I) NH4OH↔ NH4+ + OH- II) NH4Cl↔ NH4+ + Cl-
= 1,7*10-5 < 1
: (NH4OH) , .
(NH4OH) < 1 (NH4OH) = [NH4+][ OH-]/[NH4OH]
3 .
1. NaOH + - + 3→3Na + H2O
2. NaOH + - + HCl ↔ NaCl + H2O
NaOH - ( )
, .
>1 <1 >1 <1
1. NaOH + 3→3Na + H2O
Na + + OH- + 3 → 3- + Na + + H2O
OH- + 3 → 3- + H2O
>1 >1 >1 <1
2. NaOH + HCl ↔ NaCl + H2O
Na + + OH- + H+ + Cl - ↔ Na + + Cl - + H2O
OH- + H+ ↔ H2O
: . - , .
4 .
1. Pb(NO3)2 + 2KCl = PbCl2 + 2KNO3
Pb2+ + 2NO3- + 2K+ + 2Cl- = Pb2+ + 2Cl- + 2K+ + 2NO3-
( , ).
[Pb2+][2Cl-]=6,25*10-8 < PbCl2 = 2,4*10-4, .
2. Pb(NO3)2 + 2KI = PbI2↓ + 2KNO3
Pb2+ + 2NO3 - + 2K + + 2I- = PbI2↓ + 2K + + 2NO3 -
Pb2+ + 2I- = PbI2↓
( - )
[Pb2+][2I-]=6,25*10-6 > PbI2 = 8,7*10-9 , .
: ( ) ( ). > , , < , .
5 .
1. FeSO4 + Na2S → FeS↓ + Na2SO4
II II
.
|
|
Fe2+ + SO4 -2 + 2N + + S2- → FeS↓ + 2Na + + SO4 2-
Fe2+ + S2- → FeS↓
FeS↓ + 2HCl = FeCl2 + H2S
(FeS) , -, ().
FeS↓ + 2H+ + 2Cl - = Fe2+ + 2Cl - + H2S
FeS↓ + 2H+ = Fe2+ + H2S
FeS = 5*10-18
= I * II = 5,7*10-8*1,2*10-15 = 6,84*10-23
G0 = G0298(H2S) + G0298(Fe2+) - G0298(FeS) - 2 G0298(H+) = -27,97 92,26 + +100,88 0 = -19,35
G0 < 0 .
2. CuSO4 + Na2S = CuS↓ + Na2SO4
Cu2+ + SO4 2- + 2Na + + S2- = CuS↓ + 2Na + + SO4 2-
Cu2+ + S2- = CuS↓
CuS↓ + 2HCl = CuCl2 + H2S
, , , .
CuS↓ + 2H+ + 2Cl - = Cu2+ + 2Cl - + H2S
CuS↓ + 2H+ = Cu2+ + H2S
CuS = 3,2*10-38
H2S = 6,84*10-23
G0298 = G0298(H2S) + G0298(Cu2+) - G0298(CuS) - 2 G0298(H+) = -27,97 + 64,98 +
+ 53,76 2*0 = 90,77
G0 > 0 ( ).
: , , , , .