E c e l l o for reaction, 4 A l s + 3 O 2 s + 6 H 2 O + 4 O H - → 4 A l O H 4 - is 2.73 V. If G f o of O H - and H 2 O are -157 kJ m o l e - 1 and -237.2 kJ m o l - 1 determine G f o for A l O H 4 -

Step-by-step solution

For given cell reaction, ΔG o = − nE o F So, ΔG o = − 12 × 2 .73 × 96500 J = − 3.1613 × 10 3 kJ Now for given reactions, ΔG o = 4 × G f o Al OH 4 − − 6 × G f o H 2 O − 4 × G f o OH − (Also note that G f o for elements is zero) - 3.1613 × 1 0 3 = 4 G f o A l O H 4 - - 6 × - 237.2 - 4 × - 157 So, G f o Al OH 4 −   =   − 1303   kJ