Calculating the Mole Fraction of H2 in a Gas Mixture

Question:

A gas mixture contains 6.60 g of N2, 4.40 g of H2, and 15.6 g of CH4. What is the mole fraction of H2 in the mixture?

Final answer:

The mole fraction of H2 in the gas mixture is calculated by first converting the mass of each gas to moles, then dividing the moles of H2 by the total moles. This gives a mole fraction of approximately 0.645 or 64.5%

Explanation:

To calculate the mole fraction of H2, we first need to convert the given mass of each substance into moles. Using their respective molar masses (N2: 28g/mol, H2: 2g/mol, CH4: 16 g/mol), you get approximately 0.235 moles of N2, 2.20 moles of H2, and 0.975 moles of CH4.

The total moles of gas present is the sum of the moles of the individual gases, which equals 3.41 moles. The mole fraction of a particular gas is then the number of moles of that gas divided by the total number of moles. For H2, this gives a mole fraction of 2.20/3.41, approximately 0.645, or 64.5%.