The molar specific heat of oxygen at constant pressure Cp = 7.03 cal/moloC and R = 8.31 J/moloC. The amount of heat taken by 5 mol of oxygen when heated at constant volume from 10oC to 20oC will be approximately :

25 cal 50 cal 250 cal 500 cal

250 cal

\(Q = n C_V \Delta T = n(C_P - R)\Delta T\)   = \(5 (7.03 - \frac{8.31}{4.2}) (20 - 10)\)   = 250 cal