Question

The work done when $2moles$ of an ideal gas is compressed from a volume of $5m^3$ to $1d{m}^3$ at an initial temperature of $300K$, under a pressure of $100kPa$ is:

• A. $499.9kJ$
• B. $-499.9kJ$
• C. $-99.5kJ$
• D. $42495kJ$

Answer 1

The correct option is B $-499.9kJ$

$n=2$ moles

$V_1=5m^3$

$V_2=1{dm}^3={10}^{-2}{m}^3$

$T_1=300K$

$P=100K{P}_a={10}^5{P}_a$

work done $=-P\Delta V$

$={-10}^5(V_2-V_1)$

$={-10}^5({10}^{-2}-5)$

work done $=-499KJ$