(adsbygoogle = window.adsbygoogle || []).push({}); 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?

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# Homework Help: Another problem (Phase Change Heat Calculation)

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