Question

A system releases 318 kJ of heat while 289 kJ of work is done on the system. What is the change in internal energy?

Answer 1

`29 J`

Explanation:

From `1`st law of thermodynamics, we know when heat energy (`dQ`) is released from a system, the work done (`dW`) on the system, and change in its internal energy (`dU`) are related
through the following equation:

`-dQ = dU - dW`

So, `dU = dW - dQ`

`=289-318`

`=-29 J`

That means that the internal energy of the system has been decreased by `29 J`.