Answer
$T_2=365K$
Work Step by Step
For state 2, the ideal gas equation can be written as
$P_2V_2=nRT_2$
The above equation can be rewritten as:
$T_2=\frac{P_2V_2}{nR}$...............................eq(1)
Given that,
$P_2=1.5$
$P_1=1.5(20.2\times10^5)=30.3\times10^5Pa$
and $V_2=2V_1=2(0.0015)=0.003m^3$
Putting these values in eq(1) and solving:
$T_2=\frac{(30.3\times10^5)(0.003)}{(3)(8.314)}$
$T_2=365K$