posted by Boo Boo .
A sample containing 4.8 g of O2 gas has a volume of 15.0L. Pressure and temperature remain constant.
What is the volume after 4.00g of He is added to the 4.8g of O2 gas in the container
Why can't you do this the same way you did the "0.5 mol gas added to 4.8 g O2 gas"?