Question

The pressure and temperature of an ideal gas in a closed vessel are 720 kPa and ${40}^{\circ }$C respectively. If th of the gas is released from the vessel and the temperature of the remaining gas is raised to ${353}^{\circ }$C, the final pressure of the gas is

• A. 1440 kPa
• B. 1080 kPa
• C. 720 kPa
• D. 540 kPa

Answer 1

The correct option is B 1080 kPa

$P_1=720kpa,T_1=40\circ C=273+40=313K,P\propto mT\Rightarrow \frac{P_2}{P_1}=\frac{m_2}{m_1}\frac{T_2}{T_1}=\frac{3}{4}\times \frac{626}{313}=1.5\Rightarrow P_2=1.5P_1=1.5\times 720=1080kPa$