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The molar specific heat of a diatomic gas is measured at constant volume and found to be 29.1 J/mol .K. What are the types of energy that are contributing to the molar specific heat? (a) translation only (b) translation and rotation only (c) translation and vibration only (d) translation, rotation, and vibration

User Tuere
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Answer:- b

Step-by-step explanation:

The temperature of the diatomic atom's environment will vary the contributing kinetic energies for its heat capacity. At 60 K or below, the main contributor of energy is translational energy only. When the temperature rises up to about room temperature to 600 K, the contribution of rotational energy starts to be significant. When the temperature exceeds 3000 K, vibration energy is contributing to the heat capacity of a diatomic gas.

The formula for the specific heat capacity at constant volume is:

where d is for degrees of freedom.

The translational motion contribute 3 degrees of freedom, meanwhile, the rotational and vibrational motion contributes 2 each for the degrees of freedom. Having 29.1 J/mol-K as the molar heat capacity at constant volume, the equation will be:

Having the degrees of freedom = 7 means that d.) translation, rotation, and the vibration is contributing.

Answer: B

User Willlangford
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