Q64 / 75 · JEE Main 2025 (28 Jan Shift 2) · Physics
The kinetic energy of translation of the molecules in 50 g of $\mathrm{CO}_2$ gas at $17^{\circ} \mathrm{C}$ is
- A4205.5 J
- Correct answerB4102.8 J
- C3582.7 J
- D3986.3 J
Solution
Kinetic energy of translation $=\frac{3}{2} n R T$
$\begin{aligned}
& n=\frac{50 \mathrm{~g}}{44 \mathrm{~g}}=\frac{25}{22} \mathrm{~mol} \\
& T=17^{\circ} \mathrm{C}=290 \mathrm{~K}
\end{aligned}$
$\Rightarrow$ Kinetic energy of translation
$\begin{aligned}
& =\frac{3}{2}\left(\frac{25}{22}\right)(8.3)(290) \mathrm{J} \\
& =4102.8 \mathrm{~J}
\end{aligned}$
Hence, the correct answer is option: 'B'.