Finding heat of a system?

Question

A system expands by 0.61 m^3 at a constant pressure of 105 kPa.
(a)Find the heat that flows into or out of the system if its internal energy increases by 81J.
Give answer in kJ.
(b)Find the heat that flows into or out of the system if its internal energy decreases by 1440 J.
Give answer in kJ.

Answer 1

1 kPa = 9.8692×10^−3 atm
1 m^3 = 1000 L
Hence the work done by the system is:
0.61*1000*105*9.8692×10^−3 = 632 atm*L = 64.0 kJ
(a) The heat that flows into the system is:
81J + 64.0 kJ = 64.1kJ

(b) Now you should be able to solve by yourself.