Calculating Calorimeter Heat Capacity for Naphthalene Combustion

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To calculate the calorimeter heat capacity for naphthalene combustion, the user burned 136.8 mg of naphthalene, resulting in a temperature increase of 3.29 °C. They initially calculated the number of moles of naphthalene but struggled to determine the correct delta H value, questioning the accuracy of the heat of combustion they found online. The heat of combustion for naphthalene is noted as 5156 kJ/mol, which should be equated to the heat gained by the calorimeter. Despite attempts to apply this information, the user continued to encounter errors in their calculations. They plan to seek assistance from their lecturer for further clarification.
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You burn 136.8 mg of naphthalene in a calorimeter and the temperature of the calorimeter rises by 3.29 oC. Determine the calorimeter heat capacity in J K-1. The molar mass of naphthalene is 128.18 g mol-1

This is a question from a quiz I have to do.
this is wat I did.
Ccal=delta H/delta n=0.1368g/128.18g/mol
=1.06E-3moles

I don't know how to calc delta H from this info but I looked it up on the net and found 72.6+0.6kJ/mol.
Thats not right is it coz when I put this information in the formula
Ccal=((72.6+0.6)x1000j/molx1.06E-3)/(3.29+273.15)

I got it wrong... any help?
Does anyone know if my value for entropy of napthalene is right?
 
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Taryn said:
You burn 136.8 mg of naphthalene in a calorimeter and the temperature of the calorimeter rises by 3.29 oC. Determine the calorimeter heat capacity in J K-1. The molar mass of naphthalene is 128.18 g mol-1

This is a question from a quiz I have to do.
this is wat I did.
Ccal=delta H/delta n=0.1368g/128.18g/mol
=1.06E-3moles

I don't know how to calc delta H from this info but I looked it up on the net and found 72.6+0.6kJ/mol.
Thats not right is it coz when I put this information in the formula
Ccal=((72.6+0.6)x1000j/molx1.06E-3)/(3.29+273.15)

I got it wrong... any help?
Does anyone know if my value for entropy of napthalene is right?

heat of combustion of naphthelene=5156 kJ/mole. I think u may equate this to heat gained by calorimeter.
 
Thanks I will try that!
 
Yeah I just tried to use that and still got it wrong its so frustrating! I will go and see my lecturer now and hopefully he can help. Can u see anything wrong with my process?
 
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