The new pressure of the gas : 0.75 atm
Boyle's Law
At a constant temperature, the gas volume is inversely proportional to the pressure applied
[tex]\rm p_1V_1=p_2.V_2\\\\\dfrac{p_1}{p_2}=\dfrac{V_2}{V_1}[/tex]
P₁=1 atm ⇒ standart temperature and pressure (STP)
V₁=3 L
V₂=4 L
[tex]\tt P_2=\dfrac{P_1.V_1}{V_2}\\\\P_2=\dfrac{1\times 3}{4}\\\\P_2=0.75~atm[/tex]
