Question

A gas expands by 0.5 litre against a constant pressure of one atmosphere. The work done is as follows.

• A. -50.664 J
• B. -50.554
• C. 45.2 J
• D. -45.2 J

Answer 1

The correct option is A

-50.664 J

Here we know that the work done at constant pressure is given by the equation:
$w=-Pext\times \Delta V$
$\therefore w=-1\times 0.5=-0.5$ litreatm
Now we have to convert litreatm to Joules which can be done as
$=-0.5\times 101.328J$
$\therefore w=-50.664J$