On the basis of the information available from the reaction \[\frac{4}{3}Al+{{O}_{2}}\to \frac{2}{3}A{{l}_{2}}{{O}_{3}},\Delta G\] \[=-827\text{ }kJ\text{ }mo{{l}^{-1}}\] of \[{{O}_{2}}\] the minimum e.m.f required to carry out an electrolysis of \[A{{l}_{2}}{{O}_{3}}\] is \[\left( F=96500C\text{ }mo{{l}^{-1}} \right)\]

• A. 8.56 V              
• B. 2.14 V
• C. 4.28 V              
• D. 6.42 V