Question

Calculate the average kinetic energy in joule per molecule in 8.0 g of methane at ${27}^{\circ }\text{C}$

• A. $6.21\times {10}^{-19}$
• B. $6.023\times {10}^{-21}$
• C. $6.21\times {10}^{-21}$
• D. $6.21\times {10}^{-23}$

Answer 1

The correct option is C $6.21\times {10}^{-21}$

Average kinetic energy per molecule of a gas is,
$K.E=\frac{3}{2}{k}_{B}T;where,k_B=\text{Boltzmann's constant}$
$=\frac{3}{2}\times 1.38\times {10}^{-23}\times 300\text{J}=6.21\times {10}^{-21}\text{J/molecule}$