, . - -. , .
( ), ) ( )
. (...)
Δ = - > 0
> .. .
( (II)). ():
Zn - 2e = Zn+2 ()
. Cu2+ , :
Cu2++2 = Cu0 ()
, .
Zn-2e= Zn+2 ( )
Cu2++2=Cu0 ( )
Zn+ Cu2+= Zn+2+ Cu0
Zn+CuSO4 = ZnSO4+Cu
- , . .
. .. > 0, , - .
∆ = -
0Zn+2/Zn= - 0,763
0Cu2+/Cu = +0,337
= 0Cu2+/Cu - 0Zn+2/Zn = 0,337 - (-0,763) = 1,1
. G0 .
.. . , .
, , 2 :
5KI + KIO3 + 3H2SO4 = 3I2+3K2SO4+3H2O
1) , () ,
I- - e = I0
2) , () ,
I- - e = I0 5
IO3- + 6H+ + 5e = I0 + 3H2O 1
5 I- - IO3- + 6H+ = 5 I0 + I0 + 3H2O
, , , + - .
, , .
, () 250.
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0, . , .
, 0, 0. ( ) .
- . , .
: MnO4- 0 = 1,51, Cl- (0 = 1,3595) Cl2 Mn2+.
, .
(). , ΔG0298, . , 10, , , 02 , . (>0), ; <0, , , .
: Br- , , ..
2Br -+ Cl02 = Br02 + 2Cl-
0 Br2/2Br- = 1,0652 ≈ 1,07
0 Cl2/2Cl - = 1,3595 ≈ 1,36
= ∆ = 0. 0.= 1,3695 1,0652 = 0,29 > 0,
.
: Fe2+ Fe3+ 0 Fe3+/Fe2+ = 0,771, - , > 0,771.
NO3- +4H+ = NO + 2H2O, 0 = 0,968.
Fe+2 + NO3- + 4H+ → Fe3++NO+2H2O
= 0,96-0,771 = 0,19 > 0.