Consider the combustion of octane that is burned in a bomb calorimter in the presence of 10.00kg of water. When burning 8.10mL of octane (.703g/ml=d) the temp. of the surrounding water increase by 5.66°C. The heat capacity of the bomb calorimter is 6.656Kj/ °C and the water is 4.184 j/g x °C
qcal=Ccal x ΔT
ΔErxn= qrxn / moles of octane
The Attempt at a Solution
find Q of water which gave me 236.8 KJ by q=mcΔT ( m = 10000KG )
and find Q cal which ended up to 37.13 KJ by q=Ccal ΔT
then I added both Heat to get 273.9 Kj and then I divided by the number of mole found which was .049852045 moles.
However I got as an answer -5494.25 and the answer is -5506.3 Kj/mol
P.s: why does my textbook says to just use the Q of the calorimter and not add it up to the one of water in order to find the ΔE?