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Enthalpy of Combustion

Hello, I have been asked to calculate heat of combustion. I have been given a mass of calcium carbonate and a temperature rise as well as the molar heat capacity?

I am unsure what to do as I have not been given a volume/mass of water.

Thanks

Reply 1

Dat1Guy

Yeah E=mcqt you need the volume..

Reply 2

Dat1Guy

Sorry I meant q=mct my bad

Reply 3

Milliex_x

Yeah but this is not given in the question

Reply 4

Dat1Guy

Take a picture of the question?

Reply 5

Milliex_x

Original post by BDunlop

Take a picture of the question?

4g of a substance in a bomb calorimeter. The temperature rises 50 degrees celcius. The molar heat capacity is given as 81.88 JK-1mol-1

Reply 6

Dat1Guy

I don't think you can answer that, check to see if it wasn't given further up

Reply 7

Milliex_x

Original post by BDunlop

I don't think you can answer that, check to see if it wasn't given further up

If i find the volume of water. Do i just do mass x specific heat capacity of water x temperature change?

Then why would the mass of the substance and molar heat capacity be given?

Reply 8

Dat1Guy

You need to be careful, the specific heat capacity is given as per mole not per kg or g, you need to convert the volume of water into moles so that you can do no. Moles water x shc x temp rise

Reply 9

Dat1Guy

The mass of the substance would be given because you can then work out the number of moles of substance u burnt, then divide this by your total amount of energy released, to get per mole

Reply 10

Milliex_x

Original post by BDunlop

You need to be careful, the specific heat capacity is given as per mole not per kg or g, you need to convert the volume of water into moles so that you can do no. Moles water x shc x temp rise