which one of the following statements is CORRECT?

Question

a) the internal energy of a system increases when work is done on the system and heat is flowing into the system

b) the internal energy of a system increases when more work is done by the system than heat was flowing into the system

c) the system does work on the surrounding when an ideal gas compresses against a constant external pressure

d) the enthalpy of a system decreases when work is done on the system and heat is flowing into the system

e) the enthalpy of a system increases when more work is done by the system than heat was flowing into the system

Answer 1

First law of thermodynamics:

DeltaE = q + w

where E is internal energy, q is heat supplied to system, and w is work done on the system.

This should give you enough information to spot the true statement. You should also, to increase your understanding, satisfy yourself that all the other statements are false.