Determine number of moles of air.

  • Thread starter hola
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  • #1
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Suppose you want to heat the air in your house with natural gas (CH_4). Assume your house has 275 m^2 of floor are and ceilings are 2.5 m from floors. The air in your house has a specific heat capacity of 29.1 J/mol K. The number of moles in the house can be found by assuming the molar mass of air is 28.9 g/mol and that the density of the air at these temperatures is about 1.22 g/L. How much grams methane do you have to burn to heat air from 15.0 to 22.0 C?

So, here is how I think I can solve it.
1. Determine number of moles of air. I have no idea how to do that.
2. specific heat*temp*moles of CH4 = specific heat*temp*moles of water.

But I can't! Any help, please?
 

Answers and Replies

  • #2
Ouabache
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For (1) you have been given all the information except volume conversion
1 cubic meter = 1000L
 
  • #3
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Okay:
For air, I got:
Change in temp: 7.0 C
specific heat: 29.1 J/molK
mass= 839*10^5 g (should I convert this into moles?)
For methane:
specific heat: 4.18 j/molK
I need to solve for mass, right?
But I don't have temperature change in methane?

HELP! please,:smile: ?
 
  • #4
Pengwuino
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Well for one... how do you heat a house with methane without combustion????

You're missing a piece of information
 
  • #5
GCT
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2. specific heat*temp*moles of CH4 = specific heat*temp*moles of water.

why water?

First, how would you find the heat energy given off by the combustion of methane?
 

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