, . . , .
, - :
(-) Pt | H2 (p); H+(a) || Cl-(a); AgCl |Ag (+),
, . ( , , ).
. - - - , , , Zn2+ ( ), , , Cu2+ ( ):
(-) Zn | Zn2+(a 1) || Cu2+(a 2) | Cu (+).
, . , , :
(-) Cu |Zn | Zn2+(a 1) || Cu2+(a 2) | Cu (+).
Cu , . ( , , . ). , () .
,
aA Û bB
:
a Bb - D G = RT (ln Ka - ln ¾¾) a Aa |
a Bb - D G = RT ln Ka - RT ln ¾¾. a Aa |
RT ln Ka = - D G , ( ):
a Bb D G = D G + RT ln ¾¾, (10.1) a Aa |
- ( ) , .
:
- D G = w max,
, , , D G E:
D G - w max= D G = - n e FE; E = - ¾¾, (10.2) n e F |
:
D G - w max= D G = - n e FE ; E = - ¾¾, (10.3) n e F
|
n e - , , F - (F96500 /), E 0 - ( 1 , 1 / 25oC).
, (10.1) (10.2) (10.3), . (1881 .):
RT a Bb = - ¾¾ ln ¾¾, (10.4) n e F a Aa |
RT a Aa = + ¾¾ ln ¾¾, (10.5) n e F a Bb |
, , - , . , - , :
Zn0 + Cu2+ = Zn2+ + Cu0
:
RT a Cu2+ a Zn = + ¾¾ ln ¾¾¾¾ n e F a Zn2+ a Cu |
, 1,
RT a Cu2+ = + ¾¾ ln ¾¾. n e F a Zn2+ |
:
RT RT = Cu2+/Cu + ¾¾ ln a Cu2+ - Zn2+/Zn + ¾¾ ln a Zn2+, (10.6) n e F n e F |
Cu2+/Cu Zn2+/Zn - .
.
RT Cu2+/Cu = Cu2+/Cu + ¾¾ ln a Cu2+ (10.7) n e F |
RT Zn2+/Zn = Zn2+/Zn + ¾¾ ln a Zn 2+ (10.8) n e F |
. :
RT Me z +/ = Me z +/ + ¾¾ ln a Mez+ (10.9) n e F |
Me z +/ - , z+, a Me z +, Me z +/ - , a Me z + = 1 /. .
(10.6) - (10.8) , -
= Cu2+/Cu - Zn2+/Zn.
, - ,
= + - -. (10.10)
(10.10) . :
.
.
, 25 = 298 :
RT 8,314´298 0,0591 ¾¾ ln a Me z + = ¾¾¾¾¾ 2,303 lg a Me z + = ¾¾¾ lg a Me z +
n e F n e ´96500 n e |
0,0591 a Aa = + ¾¾¾ lg ¾¾, (10.11) n e a Bb |
-
0,0591 Me z +/ = Me z +/ + ¾¾¾ lg a Me z + (10.12) n e |
(10.11) (10.12) - .
, , a Me z + C Me z +, - (, , ).
RT Aa = + ¾¾ ln ¾¾ n e F C Bb |
RT Me z +/ = Me z +/ + ¾¾ ln C Me z + n e F |
( - ).
.