Flask containing greater number of molecules is — States of Matter and Gaseous State Chemistry Question

💡 Solution & Explanation

Since the masses (m) of all gases are identical, the number of moles (and thus molecules) is inversely ∝ molar mass: n = m / M. Molar masses: $H_2$ (2), $CH_4$ (16), $O_2$ (32). Flask A contains $H_2$, which has the smallest molar mass and therefore the largest number of molecules.