CHEMISTRY · Subjective · A Level · Chemistry · Amount of substance · Amount of substance
Problem
Two pure gases, X and Y, are examined separately.
• For gas X, a graph of mass versus moles passes through the points (0 mol, 0 g) and (0.250 mol, 4.00 g).
• For gas Y, the corresponding graph passes through (0.250 mol, 8.00 g).
Identify which gas is CH₄ and which is O₂. Provide your answer in the form “X is ___; Y is ___”.