If the pressure of 1.50 L of hydrogen gas at 100 °C decreases from 0.500 atm to 0.115 atm, what is the final volume? Assume temperature remains constant at 3.45 L.

${P}_{1} {V}_{1} = {P}_{2} {V}_{2}$. ${V}_{2} \cong 6 \cdot L$
${V}_{2} = \frac{{P}_{1} {V}_{1}}{P} _ 2$ (and this will clearly give us an answer with units of volume as required.)
V_2=(0.500*atmxx1.50*L)/(0.115*atm)=???