In a diatomic molecule, the rotational energy at given temperature

Options

A. Obeys Maxwell's distribution
B. Have the same value for all molecules
C. Equals the translational kinetic energy force molecule
D. Is (2/3) rd the translational kinetic enery each molecule

Answer

A, D

Explanation

Sol, (a,b) According to the problem we have to find rotational energy of a diatomic molecule in the terms of translation kinetic energy.
First let us cheej the option by picking them one by one.
(a) Translational kinetic energy and rotational kinetic energy both obey Maxwe It's distribution independent of each other.
(b) Molecules os ideal gases possess only translational motion. so they possess only translational kinetic energy. But in case of non-ideal gas there is a smaller rotational energy.
(d) Here, 2 rotational and 3 translational energies are associated with each molecule. Translation kinetic energy of each molecule,
`K_(T)=(3)/(2)KT`, whre K is constant
Rotational Kinetic energy, `K_(R)=2((1)/(2)KT)`On viding these two equtions, we get
`(k_(R))/(k_(T))=((k^(T)))/((3)/(2)k^(T))rArrK_(R)=(3)/(2)k_(T)`

`therefore` Rotational energy at a given temperature `((2)/(3))` rd of translational KE of each molecule.