Why is the eqn written like that ? Q 27. write the Nernst equation and the emf of the following cells at
Pt(s) I I Bö(O.010 M) II (0.030 M) I H2(g) (1 bar) I Pt(s)
-+1.08 v.
Given, E112Br:/Br-
AL Cellreaction: 2Br- + Br2 + H 2 ; n =
0.0
log
Nernst equation: E cell = Ecell —
[BO 12 [H+12
2
0.0591
log
-(0 - 1.08) -
Ecell -
1
(0.01)2 (0.03)2
2
0.0591
log (1.111 x 107)
As
is
=-1.08 -
1.08 -
negativ
2
0.0591
(7.0457)
2
1.08 - 0.208 1.288 v
