Question

hi guys need little help...a system gains 622kj of heat, resulting in a change in internal energy of the system equal to +156kj. how much work is done?

Answer 1

Note that: \(\sf \color{red}{\Delta E = q + w}\)
where q= heat
w = work
and \(\sf \Delta\)E = change in energy

So, if you rearrange the given equation to solve for \(w\), you should get: \(\sf \color{blue}{w = \Delta E - q }\)

Now, plug and solve.

Answer 2

\(\sf \color{red}{NOTE}\): keep in mind the symbol of heat, \(q\), when doing these types of problems. It can either be +q or -q, depending whether the system is gaining or expending energy.