, (23, MgCl2, CH3COONa, FeSO4 .) . .
, , .
: - :
CO32- + H-OH ⇄ CO3- + -,
:
Fe3+×nH2O + H-OH ⇄ FeOH2+×(n-1)H2O + 3O+.
, , - .
:
H2O ⇄ + + -.
+ -, .
.
, (Na2SO4, CaCl2, KI, Sr(NO3)2 .), , . ( = 7).
.
1. , (CH3COONa, KCN, Ca(OCl)2, NaF .).
. .
, (Na2S, Na2CO3, K3PO4, Na2SO3 .), , .
1. CH3COONa.
(CH3COOH) (NaOH). (CH3COO-) :
CH3COONa + H-OH ⇄ CH3COOH + Na, pH > 7;
- :
CH3COO- + H-OH ⇄ CH3COOH + -.
3 + -. + 3- CH3COOH - , , .
2. K2S.
(S2-) :
:
K2S + H-OH ⇄ KHS + K, pH > 7,
S2- + H-OH ⇄ HS- + -;
:
KHS + H-OH ⇄ H2S + K,
HS- + H-OH ⇄ H2S + -.
, .
2. , (NH4C1, FeSO4, ZnCl2 .).
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. .
, , , - .
3. Zn(NO3)2.
(HNO3) (Zn(OH)2). (Zn2+) :
:
Zn(NO3)2 + H-OH ⇄ ZnOHNO3 + HNO3, pH < 7,
Zn2+ + H-OH ⇄ ZnOH+ + H+;
:
ZnOHNO3 + H-OH ⇄ Zn(OH)2 + HNO3,
ZnOH+ + H-OH ⇄ Zn(OH)2 + H+.
4. Cr2(SO4)3.
(r3+) :
:
Cr2(SO4)3 + 2H-OH ⇄ 2CrOHSO4 + H2SO4, pH < 7,
Cr3+ + H-OH ⇄ CrOH2+ + H+;
:
2CrOHSO4 + 2H-OH ⇄ [Cr(OH)2]2SO4 + H2SO4,
CrOH2+ + H-OH ⇄ Cr(OH)2+ + H+;
:
[Cr(OH)2]2SO4 + 2H-OH ⇄ 2Cr(OH)3 + H2SO4,
Cr(OH)2+ + H-OH ⇄ Cr(OH)3 + H+.
( ) .
3. , (NH4CN, CH3COONH4, (NH4)2S, (NH4)2CO3 .).
, , . :
) 
> 
, ;
) < , ;
) = , .
5. CH3COONH4.
(CH3COOH) (NH3∙H2O). c :
CH3COONH4 + H-OH ⇄ NH3×H2O + CH3COOH,
CH3COO- + NH4+ + H-OH ⇄ NH3×H2O + CH3COOH.
(NH3×2) = 1,8×10-5;
(3) = 1,8×10-5,
pH 7 ( ).
6. (NH4)2O3.
:
:
(NH4)2O3 + H-OH ⇄ NH3×H2O + NH4HO3,
NH4+ + O32- + H-OH ⇄ NH3×H2O + HO3-;
:
NH4HO3 + H-OH ⇄ NH3×H2O + H2O3,
NH4+ + HO3- + H-OH ⇄ NH3×H2O + H2O3.
(NH3×2) = 1,8×10-5,
(23) = 3,7×10-7,
(23) = 4,7×10-11,
pH > 7 ( ).
, , , , (. . , ). , . , + -, .
(. . ) , . . , . , (), - ().
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7. Al2S3 ( ).
:
Al2S3 + 6H2O = 2Al(OH)3¯ + 3H2S
, .
8. Na2CO3 FeCl3. .
, .. . , , . . - (III) Fe(OH)3 2:
3Na2CO3 + 2FeCl3 + 3H2O = 2Fe(OH)3¯ + 3CO2 + 6NaCl
3O32- + 2Fe3+ + 3H2O = 2Fe(OH)3¯ + 3CO2
