For the reaction
3 Ni2+(aq) + 2 Cr(OH)3(s) + 10 OH- (aq)  →  3 Ni(s) + 2 CrO42-(aq) + 8 H2O(l) G = +87 kJ/mol
Given:
(Ni2+(aq) + 2 e- →  Ni(s)) x 3 Ered = -0.28 V
(CrO42-(aq) + 4 H2O(l) + 3 e- →  Cr(OH)3(s) + 5 OH-(aq)) x 2
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3 Ni2+(aq) + 6 e- →  3 Ni(s)
2 CrO42-(aq) + 8 H2O(l) + 6 e- →  2 Cr(OH)3(s) + 10 OH-(aq)