This question is considered one of the hardest in this chapter regarding thermodynamics. I spent countless time trying to figure it out but i was never close to the answer. The question is: Water is heated in an open pan where the air pressure is 1atm. WAter remains a liquid but expanded by a small amount when it was heated. FIND THE RATIO OF WORK DONE BY WATER TO THE HEAD ABSOBED BY THE WATER. So that means: W / Q where W = P(Vf - Vi) but what's Q? I tried Q = cm delta T but i was wrong. if anyone can help me i'd appreciate it thanks.