What is the heat of combustion of methane? Include the sign in your answer.?

A 4.69 g sample of propane, C3H8, is burned in excess oxygen producing carbon dioxide gas and liquid water. The reaction occurs in a calorimeter surrounded by 1.52 kg of water resulting in a temperature change from 23.9°C to 50.1°C. What is the heat of combustion of methane? Include the sign in your answer. Assume the heat released by the reaction is completely asborbed by the water.


I got -128.8 But that was wrong.





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What is the heat of combustion of methane? Include the sign in your answer.?
Methane's heat of combustion is approximately 802 kJ/mol, I believe; the lowest of any hydrocarbon.
Reply:why don't u learn to do it yourself, and u might score in the 700's in the sat ii's. Or if u dont wanna do it urself, consider failing the regents(or whatever state test on chem) as an option