Atoms, molecules and stoichiometry — practice question

Which contains the largest number of the named particles?

• A$6.0\,\text{dm}^3$ of argon atoms at room conditions
• B$6.0\,\text{g}$ of carbon dioxide molecules
• C$6.0\,\text{g}$ of magnesium atoms
• D$6.0\,\text{g}$ of water molecules