Answer
The SI units of $PV$ are joules.
Work Step by Step
Pressure is measured in units of $N~m^{-2}$ which can be expressed as $kg~m^{-1}~s^{-2}$
Volume is measured in units of $m^3$
We can find the units of $PV$:
$(kg~m^{-1}~s^{-2})(m^3) = kg~m^2~s^{-2} = joules$
The SI units of $PV$ are joules.
