“…The molar heat capacity of a gas consists of translational, rotational, and vibrational parts: In the case of hydrogen with diatomic molecules there is no appreciable occupation of higher vibrational states for temperatures below 1000 K (T vib = 6320 K). Thus, the vibrational part (c Vib V ;m ) can be neglected [4]. The translational part (c Trans V ;m ) of a (quasi) ideal gas is equal to 3 2 R (3 translational degrees of freedom × ½R = 12.5 J mol 1 K 1 ).…”