Question

The kinetic energy of 1 g molecule of a gas at normal temperature and pressure is $ (R=8.31\,J/mol-K) $

• A. $ 3.4\times {{10}^{3}}J $
• B. $ 2.97\times {{10}^{3}}J $
• C. $ 1.2\times {{10}^{2}}J $
• D. $ 0.66\times {{10}^{4}}J $

Answer 1

Answer: (A)

$ E=\frac{l}{2}m{{v}^{-2}} $ $ =\frac{1}{2}M\left( \frac{3RT}{M} \right) $ $ E=\frac{3}{2}RT $ $ E=\frac{3}{2}\times 8.31\times 273 $ $ E=3.4\times {{10}^{3}}J $