Question

When temperature is increased from $0^{\circ }C$ to $273^{\circ }C$, in what ratio the average kinetic energy of molecules change ?

• A. 1
• B. 3
• C. 4
• D. 2

Answer 1

Answer: (D)

The average kinetic energy $(KE)$ is given by
$KE=\frac{3}{2}kT$
where $T$ is absolute temperature.
$\therefore \frac{K{E}_1}{K{E}_2}=\frac{T_1}{T_2}$
Given, $T_1=0^{\circ }C=273K$,
$T_2=273^{\circ }C=546K$
$\Rightarrow \frac{E_2}{E_1}=\frac{T_2}{T_1}=\frac{546}{273}$
$=2$