1. The problem statement, all variables and given/known data 2. Relevant equations q = mcat mols*hvap 3. The attempt at a solution To decrease temp from 70 to 56 degrees (bp), q=mcat = 1195.5 to convert this gas into liquid , must do mols * hvap = 29129 joules to decrease temp from 56 to 0 thought, i get q= mcat = -7047 J (which is negative- is this wrong?) it seems like the correct answer is when 7047 is positive after adding these up,. i get 37.37 kj. which seams like the answer (cant see it cause my professor erased it...) Why wouldn't i subtract the last number?