Question

1) A 3.00-mol sample of an ideal diatomic gas in which the gas particles both translate and rotate is initially at 600 K. Energy is then added thermally to the sample until its temperature is 1000 K. Assume that at the temperatures higher than 1000 K, the particles also vibrate, at the temperatures lower than 1000 K, the particles do not vibrate. The sample is then heated to 1200 K.

Part A:- How much thermal energy does the sample absorb? Express your answer with the appropriate units.

Answer 1

The energy of a diatomic molecule is, K-RT The degrees of freedom for a diatomic molecule with rotational and translational modes are 5. So, energy is, K- The degrees of freedom for a diatomic molecule with vibrational, rotational and translational modes are 7. So, energy is, K-RT 2 2 2 The thermal energy absorbed by the sample will be, 2 2 Substitute the values, AK + дк,-G mol)( 8.3 14 J/mol . K)| 1200 K-1000 K)-(1000 K-600 K) 2 4.24 x104 J