Answer:
[tex]MM_{mixture}=9.68g/mol[/tex]
Explanation:
Hello!
In this case, since the molar mass of gaseous mixtures can be determined via a weighted average containing the molar mass of each gas and the mole fraction (mole percent divided by 100) as shown below:
[tex]MM_{mixture}=x_{CO_2}M_{CO_2}+x_{N_2}M_{N_2}+x_{He}M_{He}[/tex]
Now, we plug in to obtain:
[tex]MM_{mixture}=0.11*44g/mol+0.053*28+0.84*4\\\\MM_{mixture}=9.68g/mol[/tex]
Best regards!