A chemical reaction is run in which 596 Joules of work is done on the system and the internal energy changes by + 966 Joules. Calculate q for the system.

Question

A chemical reaction is run in which 596 Joules of work is done on the system and the internal energy changes by + 966 Joules.

Calculate q for the system.

Answer 1

∆U = q + w

∆U = change in internal energy = +966 J

q = heat = ?

w = work = +596 J (positive because work is done ON the system

966 J = q + 596 J

q = 966 J - 596 J

q = 370 J (positive because heat is add to the system; endothermic)