Question

How much heat would be absorbed by 2 litres of an ideal gas at 5 atm pressure if it expands isothermally into an evacuated flask of 5 litres

Answer 1

Explanation:

Since, it is given that it is an isothermal process and for an isothermal process value of $\Delta U$ (internal energy) is zero.

Hence, work done by the gas in an isothermal process will be as follows.

             w = $-P_{ext} \Delta V$

As it is an evacuated system so, gas will expand and therefore, work will be done by the system.

Here,  $P_{ext}$ = external pressure of the system = 0

Therefore, putting the values into the above formula as follows.

                      w = $-P_{ext} \Delta V$

                          = $- 0 \times (5 - 2)$

                           = 0

Relation between heat and work is as follows.

                 $\Delta U$ = q + w

                              0 = q + 0

                               q = 0

Thus, we can conclude that no heat would be absorbed by given system.

If T=300K then

W=2.3026×8.31 log 2.5

=2284 J

Heat absorbed is equal to the work done.

Answer 2

Answer:

No heat absorbed

Explanation:

See the pic attached

Peace out ✌