josephinemar25
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Report Thread starter 6 years ago
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Hi guts can you help me out with this question:
In an experiment 0.16g of methanol is burnt CH3OH to heat a 100g of water from 17 to 24 celcius. Calculate the enthalpy change for the combustion of methanol?
the answer should be: -585KJmol-1

what I have done so far:
E=MCdeltaT
Energy transferred = 100gx 4.18x-7=-2926J=-2.296KJ
moles of fuel burnt=0.16/32= 0.005
Enthalpy change for combustion= -2.296/0.005=-459.2
why is this not right?? please explain
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Whateverisbest
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Your mass is suppose to be in kg, not grams.
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