[sn1sn2e1e2]

Given the standard reduction potentials:

 O2 + 4H+ + 4e- --> 2H2O E* = 1.23 V
 Br2 + 2e- --> 2Br- E* = 1.08 V
 2H+ + 2e- --> H2 E* = 0.00 V
 Na+ + e- --> Na E* = -2.71 V

What products are formed in the electrolysis of 1 M NaBr in a solution with [H3O+] = 1 M?

(A) Na (s) and O2(g)
(B) Na (s) and Br2 (g)
(C) H2 (g) and Br (g)
(D) H2 (g) and O2 (g)

Since electrolysis, ΔG is not spontaneous and E cell has to be negative, right? So why can't it be B since adding the E of the half reaction result in -3.79 volts (non spontaneous)? (The correct above is (C))

[sjb]

Does sodium react with water?

[sn1sn2e1e2]

Na + H2O  Na+  OH-   H2

[cheah10]

You have to know that for electrolysis, the more positive the E cell is, the more likely the reaction will happen, not the more negative.