The initial volume of a gas cylinder is $$750.0$$  $$mL.$$  If the pressure of gas inside the cylinder changes from $$840.0\,mm\,Hg$$    to $$360.0\,mm\,Hg,$$    the final volume the gas will be :

Solution :
$$\eqalign{ & {\text{According to Boyle}}'{\text{s}}\,\,{\text{law}} \cr & \frac{{{V_1}}}{{{V_2}}} = \frac{{{P_2}}}{{{P_1}}};\,\frac{{750}}{{{V_2}}} = \frac{{360}}{{840}} \cr & {V_2} = 1750\,mL = 1.750\,L \cr} $$