Calorimetry problem

Question

Calculate the internal energy (in Joules) of a system that loses 288.0 J that is compressed with a pressure of 2.60 atm from 8.160 L to 1.00 L. 

Answer 1

∆U = q - w

Change in internal energy = heat - work

work = P∆V = pressure x change in volume = 2.60 atm x (1.00 - 8.160) = -18.6 Latm

q = -288.0 J

∆U = -288.0 J - (-18.6 Latm) and since 1 Latm = 101.3 J, we have ...

-18.6 Latm x 101.3 J/Lat = -1886 J

∆U = -288 J + 1886 J

∆U = 1598 J