Correct answer: 1500 kilo calorie
For \(N_2\) at 27°C, vibrational modes are not active, so a diatomic gas has 5 active degrees of freedom. Thus the total kinetic energy is \(\frac{5}{2}RT\), which is about \(1.5\times 10^3\) kcal for 1 mole at 300 K.