question_answer

In a fuel cell methanol is used as fuel and oxygen gas is used as an oxidizer. The reaction is \[C{{H}_{3}}OH(l)+3/2{{O}_{2}}(g)\xrightarrow[{}]{{}}C{{O}_{2}}(g)+2{{H}_{2}}O(l)\] At 298 K standard Gibb?s energies of formation for\[C{{H}_{3}}OH(l),{{H}_{2}}O(l)\]and\[C{{O}_{2}}(g)\]are -166.2, - 237.2 and -394.4 kJ \[mo{{l}^{1}}\]respectively. If standard enthalpy of combustion of methanol is\[726\text{ }kJ\text{ }mo{{l}^{1}},\] efficiency of the fuel cell will be:     AIEEE  Solved  Paper-2009

A) 80%                                       

B) 87%

C) 90%                       

D)        97%