- #1

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## Homework Statement

## Homework Equations

M=m/n

p=nRT/V

## The Attempt at a Solution

I am confused on getting the molar mass of the mixture, unless the answer is wrong.

For n

_{N2}I done 0.79*(3*10

^{-3}) which gave me 2.37*10

^{-3}kmol

For n

_{O2}I done the same but with 0.21 to get 6.3*10

^{-4}kmol

The n

_{total}of the mixture is 3.5*10

^{-3}kmol

For each pressure I used p=nRT/V with R=8314 to get 174.594kPa for the total pressure, 31.427kPa for the partial pressure of oxygen, and 118.225kPa for nitrogen.

But when working out the partial pressure of CO

_{2}I got 24.942kPa. In the answers it states it is actually meant to be 29.94kPa but unless this is a mistake, I am not sure why it would be this.

Lastly for the Molar mass, I done (m

_{O2}/n

_{total})+(m

_{N2}/n

_{total})+(m

_{CO2}/n

_{total}) to find the total molar mass, and that gave me 14.455kg/kmol, when it should apparently be 31kg/kmol.

I done 1/3*(0.5*10

^{-3})(16) to find the mass of Carbon and used 2/3 for the mass of Oxygen in the CO

_{2}.