One mole of an ideal gas at 300 K and 20 atm expands to 2 atm under isothermal and reversible conditions. The work done by the gas is $-x \mathrm{~kJ} \mathrm{~mol}^{-1}$. The value of $x$ is $\left(\mathrm{R}=8.3 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}\right)$

• Correct answer
  A

  $5.73$
• B

  $7.37$
• C

  $3.75$
• D

  $4.57$

Hence, the correct answer is option: 'A'.