Q40 of 62 Page 72

The difference between CPand CV can be derived using the empirical relation H = U + PV. Calculate the difference between CP and CV for 10 mole of an ideal gas.

o CP is the heat capacity at constant pressure and CV is the heat capacity at constant volume.


o For an ideal gas, the difference between these two is CP - CV = nR, the universal gas constant and where n= no. Of moles.


o Hence for 10 moles of an ideal gas CP - CV = 10 R


= 10 × 8.314 J


= 83.14 J


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