Question

A scuba tank contains 20.0 L of air at 30°C and 1.5 atm. Assuming that the temperature remains constant, what volume of air is required to fill the tank to a pressure of 40 atm? 

Answer 1

$V_1=20L,P_1=1.5atm , P_2=40 atm$

using Boyle's law-

$P_1V_1=P_2V_2 \\[9pt] \Rightarrow 20\times 1.5=V_2\times 40 \\[9pt] \Rightarrow V_2=\dfrac{30}{40}=0.75L$