Finding Number of Moles with Ideal Gas Equation

[jimmy42]

I want to find the number of moles and I have the ideal gas equation as :

n = PV/RT

However I think I'm using the wrong units to find it, I want the answers in moles.

n = (1 Pa * 1 m^3) /(8.314 JK^-1 mol^-1 * 1K)

so would this give the answer x mol^-1??

I can't see how that would be.

Thanks.

 

[gneill]

Where's the mol^-1 in the formula? What's

$$\frac{1}{a^{-1}} = ?$$

 

[jimmy42]

Doesn't that just equal a? Not sure how that helps?

Isn't 1Pa * 1m^3 = 1 Pa m^3??

 

[Dadface]

n gives the number of moles and you are using the right units.

 

[rwisz]

I can confirm that your equation is correct for calculating the number of moles using the ideal gas equation. However, the units you are using are not consistent and may result in an incorrect answer. In order to get the answer in moles, you need to use consistent units for pressure, volume, temperature, and the gas constant.

For pressure, it is recommended to use units of atmospheres (atm) or kilopascals (kPa). For volume, it is recommended to use units of liters (L) or cubic meters (m^3). For temperature, it is recommended to use units of Kelvin (K). And for the gas constant, it is recommended to use units of liters*atm/mol*K or joules/mol*K.

Once you have consistent units, you can plug in the values and solve for the number of moles. Remember to also check that the units cancel out correctly to give you moles as the final unit.

I hope this helps clarify any confusion and assists you in finding the correct answer. As always, double check your units and calculations to ensure accuracy. Happy experimenting!