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# Enthalpy of Combustion watch

1. 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
2. Yeah E=mcqt you need the volume..
3. Sorry I meant q=mct my bad
4. Yeah but this is not given in the question
5. Take a picture of the question?
6. (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
7. I don't think you can answer that, check to see if it wasn't given further up
8. (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?
9. 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
10. 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
11. (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
But the heat capacity given is for the substance. Isn't the specific heat capacity of water used in that equation?

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