The molar heat of combustion for phenol

AI Thread Summary
The discussion focuses on calculating the molar heat of combustion for phenol using a calorimeter. The initial calculations involved determining the number of moles of phenol burned and applying the heat capacity formula. A clarification was provided regarding the use of temperature change, confirming that the Celsius and Kelvin scales are equivalent for temperature differences. After addressing the confusion, the original poster successfully arrived at the correct answer. The interaction highlights the importance of understanding thermodynamic principles in calorimetry.
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You burn 103.4 mg of phenol in a calorimeter of heat capacity 1,483 J K-1 and the temperature rises by 1.83 oC. Determine the molar heat of combustion for phenol in kJ mol-1. The molar mass of phenol is 94.12 g mol-1

Ccal=deltaH/ deltaT

This is what I did.
n=.1034/94.12
=1.09859E-3mol

deltaH=(1483J/K*274.98K)/1.09859E-3
deltaH=371198.84kJ/mol

What did I do wrong... any help would be appreciated. thanks!
 
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Your equation calls for deltaT, so that means the change in temperature.

You were given deltaT in the question. Remember that 1 degree Celcius = 1 degree Kelvin, so the difference of two temperatures will be the same on either scale.
 
Hey Thanks... that's helpful... I got the answer to the answer right thanks a heap!
 

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