Solving Unknown Quantity of Gas: Help Appreciated!

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If anyone has time, could you please show me the working of this problem.

Greatly appreciated


b]1. Homework Statement [/b]
If I have an unknown quantity of gas at a pressure of 1.2 atm, a volume of 31 liters, and a temperature of 87C, how many moles of gas do I have?


Homework Equations



PV=nRT=NkT

The Attempt at a Solution



1.2 x 31=n8.3145 x (87+273)= N x 1.38066x10*23 x (87+273)

Can you tell me if the above numbers are correct please.
 

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chawkdee said:
If anyone has time, could you please show me the working of this problem.

Greatly appreciated


b]1. Homework Statement [/b]
If I have an unknown quantity of gas at a pressure of 1.2 atm, a volume of 31 liters, and a temperature of 87C, how many moles of gas do I have?


Homework Equations



PV=nRT=NkT

The Attempt at a Solution



1.2 x 31=n8.3145 x (87+273)= N x 1.38066x10*23 x (87+273)

Can you tell me if the above numbers are correct please.
You have to stick to MKS units. Volume has to be in m^3 not litres. Otherwise, it looks fine.

AM
 
The pressure should be in pascals as well.
 
phsopher said:
The pressure should be in pascals as well.

Of course! Thanks for catching that.

AM
 
chawkdee said:
... how many moles of gas do I have?


Homework Equations



PV=nRT=NkT

Given what is being asked, would you use nRT or NkT here?
 
Redbelly98 said:
Given what is being asked, would you use nRT or NkT here?

nRT ??
 
Why do you think that ... or is it just a random guess? The key here is: what do n and N mean?
 
Redbelly98 said:
Why do you think that ... or is it just a random guess? The key here is: what do n and N mean?

n - number of moles

N - number of molecules
 
Okay, yes. n is the number of moles, so PV=nRT is the thing to use here.

Just be careful with the units, as others said earlier.