Answer: The mole fractions of He in the mixture is 0.992.
The mole fraction of
in the mixture is 0.008.
Explanation:
A gas mixture called heliox, 6.11%
and 93.89% He gas by mass by mass.
Percentage of oxygen gas in a mixture by mass = 6.11%
In 100 gram mixture 6.11% of oxygen is present by mass :![\frac{100\times 6.11}{100}=6.11 grams](https://tex.z-dn.net/?f=%5Cfrac%7B100%5Ctimes%206.11%7D%7B100%7D%3D6.11%20grams%20)
Percentage of helium gas in a mixture by mass = 93.89%
In 100 gram mixture 93.89% of helium is present by mass :![\frac{100\times 93.89}{100}=93.89 grams](https://tex.z-dn.net/?f=%5Cfrac%7B100%5Ctimes%2093.89%7D%7B100%7D%3D93.89%20%20grams%20)
Mole fraction of component 'x' in a mixture of 'x' and 'y'= ![=\chi _x=\frac{n_x}{n_x+n_y}](https://tex.z-dn.net/?f=%3D%5Cchi%20_x%3D%5Cfrac%7Bn_x%7D%7Bn_x%2Bn_y%7D)
= moles of gas 'x'=![\frac{\text{mass of gas 'x'}}{\text{Molar mass of gas 'x'}}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Ctext%7Bmass%20of%20gas%20%27x%27%7D%7D%7B%5Ctext%7BMolar%20mass%20of%20gas%20%27x%27%7D%7D)
= moles of gas 'y'=![\frac{\text{mass of gas 'y'}}{\text{Molar mass of gas 'y'}}](https://tex.z-dn.net/?f=%5Cfrac%7B%5Ctext%7Bmass%20of%20gas%20%27y%27%7D%7D%7B%5Ctext%7BMolar%20mass%20of%20gas%20%27y%27%7D%7D)
Moles of oxygen gas ,when 6.11 grams of oxygen in present in a mixture:
![n_{O_2}=\frac{6.11 g}{16g/mol}=0.3818 moles](https://tex.z-dn.net/?f=n_%7BO_2%7D%3D%5Cfrac%7B6.11%20g%7D%7B16g%2Fmol%7D%3D0.3818%20moles)
Moles of helium gas ,when 93.89 grams of helium in present in a mixture:
![n_{He}=\frac{93.89 g}{2g/mol}=46.945 moles](https://tex.z-dn.net/?f=n_%7BHe%7D%3D%5Cfrac%7B93.89%20g%7D%7B2g%2Fmol%7D%3D46.945%20moles)
![=\chi _{O_2}=\frac{n_{O_2}}{n_{O_2}+n_{He}}=\frac{0.3818 mol}{0.3818 mol+46.945 mol}=0.008](https://tex.z-dn.net/?f=%3D%5Cchi%20_%7BO_2%7D%3D%5Cfrac%7Bn_%7BO_2%7D%7D%7Bn_%7BO_2%7D%2Bn_%7BHe%7D%7D%3D%5Cfrac%7B0.3818%20mol%7D%7B0.3818%20mol%2B46.945%20mol%7D%3D0.008)
![=\chi _{He}=\frac{n_{He}}{n_{O_2}+n_{He}}=\frac{46.945 mol}{0.3818 mol+46.945 mol}=0.9919\approx 0.992](https://tex.z-dn.net/?f=%3D%5Cchi%20_%7BHe%7D%3D%5Cfrac%7Bn_%7BHe%7D%7D%7Bn_%7BO_2%7D%2Bn_%7BHe%7D%7D%3D%5Cfrac%7B46.945%20mol%7D%7B0.3818%20mol%2B46.945%20mol%7D%3D0.9919%5Capprox%200.992)
The mole fractions of He in the mixture is 0.992.
The mole fraction of
in the mixture is 0.008.