Question

Under which of the following conditions is the relation,

$△H=△U+P△V$ valid for a closed system?

• A. Constant pressure
• B. Constant temperature
• C. Constant temperature and pressure
• D. Constant temperature, pressure and composition

Answer 1

The correct option is A Constant pressure

$\Delta H=\Delta U+\Delta \left(PV\right)$

$⟹\Delta H=\Delta U+P\Delta V+V\Delta P$

In constant pressure/ Isobasic process

$⟹\Delta H=\Delta U+P\Delta V$