1. The problem statement, all variables and given/known data Do 5 L of Ne contain the same number of particles contained in 5 L of O ? 2. The attempt at a solution The book say yes but I know that 5 L of Neon are 4.5 g and 5 L of Oxygen are 7.15 g. So dividing them for their molecular weight I obtain 0.22 u and 0.44 u that aren't tha same :( Where do I wrong? Thank you!