What is the volume at 0 °C and 1 atm of a mixture that contains 4.0 g of methane and 2.0 g of helium?
The volume of the sample is 16.8 L.
- Convert the mass of each gas to litres
- Use the molar volume of each gas at STP to calculate its volume.
- Add the two volumes.
Moles of CH₄ = 4.0 g CH₄ ×
Moles of He = 2.0 g He ×
Volume of CH₄ = 0.25 mol CH₄ ×
Volume of He = 0.50 mol He × ×
Total volume = (5.6 + 11.2) L = 16.8 L