We know by Gay Lussac's law that volume remaining consant , the pressure of the given mass of a gas is directly proportional to its Kelvin temperature ,
P∝T ,
if P1= initial pressure of a gas ,
P2= final pressure of gas ,
T1= initial temperature of gas ,
T2= final temperature of gas , ,
then P2/P1=T2/T1 ,
given T1=0+273=273K , T2=273+273=546K ,
and volume is constant because gas is in a closed container ,
therefore P2/P1=546/273=2 ,
P2=2P1 ,
pressure of gas will be doubled.