When a system is taken from state ‘x’ to state ‘y’ then 30 kJ of heat flows into the system and the system does 10 kJ of work. When the system is returned from state ‘y’ to state ‘x’ along another path, then work done on the system is 8 kJ. What is the amount of heat liberated?

When a system is taken from state ‘x’ to state ‘y’ then 30 kJ

1.	When a system is taken from state ‘x’ to state ‘y’ then 30 kJ of heat flows into the system and the system does 10 kJ of work. When the system is returned from state ‘y’ to state ‘x’ along another path, then work done on the system is 8 kJ. What is the amount of heat liberated?
A.	12 kJ of heat liberated
B.	28 kJ of heat liberated
C.	12 kJ of heat absorbed
D.	28 kJ of heat absorbed
Answer» C. 12 kJ of heat absorbed