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question help (1 Viewer)

rubyp

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The question is: using the figure of 1372 kJ.mol-1 for the molar heat of combustion of ethanol, calculate the heat produced from the combustion of 2 moles of this alcohol.

I'm just a little unsure of the steps I have to take
 

KingOfActing

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1372 kJ of heat is produced for every mole that undergoes combustion, therefore 2*1372 = 2744 kJ of heat is produced for 2 moles.
 

Shoesta

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Ruby as if you wouldn't get this... You would if you were good at Chemistry.
 

rubyp

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thank you! I thought it was a trick question :lol:
 

Shoesta

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1372 kJ of heat is produced for every mole that undergoes combustion, therefore 2*1372 = 2744 kJ of heat is produced for 2 moles.
How many moles of ethanol will need to be burnt to produce 4459kJ of heat?
 

ml125

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Okay, 1 more...

How do you do the calculations for the molar heat of combustion for propanol 1 and heptanol 1??

Thanks heaps!!!!!
It's basically the same as molar heat of combustion for ethanol

1. Find the heat of reaction (ΔH = mcΔT)
2. Divide by mass of alkanol used (to get ΔH/g)
3. Multiply (2) by molar mass of alkanol (to get ΔH/mol)
 

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