Chemistry Stoichiometry Practice Quiz

Mole and Volume Relationships

• If the volume of oxygen (O2) is half the volume of carbon dioxide (CO2), the moles of oxygen and carbon dioxide present are in a 1:2 ratio.
• The number of carbon atoms in 1 mole of propane is approximately 3.612 × 10^24.

Stoichiometry

• In the reaction N2 + 3H2 → 2NH3, 1 L of nitrogen reacts with 3L of hydrogen at room temperature and pressure, forming 2L of ammonia.
• The reaction follows a 1:3:2 mole ratio.

Avogadro's Law

• Samples of elements containing the same number of atoms are 2g of calcium, 1g of lithium, 2g of sodium, and 24g of Mg.
• These samples contain 1 mole of each element.

Mole and Mass Relationships

• The mass of 1 mole of H2 is 2g, not 1g.
• The mass of 1 mole of N2 at STP is 28g.
• One mole of any gas at STP occupies 22.4 L volume.

Gas Laws

• For a fixed number of molecules of a gas, if the volume is changed, the temperature will change accordingly.
• The temperature of a gas is directly proportional to its volume.

Mole Calculations

• The maximum number of moles present in 5.4 g of aluminium (Al) is 0.2 moles.
• The number of atoms in 20 g of Ca is approximately 6.023 × 10^23.

Molecule Mass

• The mass of one molecule of methyl alcohol (CH3OH) sample at STP is 3.20 × 10^-23 g.