Answer:
This is a simple example of Charles' law
V1T1=V2T2,
which states that the volume of a gas is directly proportional to its temperature in K.
We know V1 = 4.5L, T1=(25+273.15)=298.15K, and V2 = 9L, therefore
T2=V2V1⋅T1=94.5⋅298.15=596.4K -> double the volume translates to double the temperature, and vice versa.
