Relative mass comparison – O2 molecule vs. H atom By what factor is the mass of one molecule of oxygen (O2) greater than the mass of a single hydrogen atom (H)?

Introduction / Context:
Quick mass ratios are handy in reaction stoichiometry and gas property calculations. Comparing molecular and atomic masses by simple factors builds intuition for molar mass and mixture behavior in thermodynamics and chemistry problems.

Given Data / Assumptions:

• Atomic mass of hydrogen (H) ≈ 1 u (relative atomic mass scale).
• Atomic mass of oxygen (O) ≈ 16 u.
• Molecule considered: O2 (diatomic oxygen), so molecular mass ≈ 32 u.

Concept / Approach:

Since an O2 molecule consists of two oxygen atoms, its mass is roughly 2 * 16 u = 32 u. Dividing by the mass of a hydrogen atom (≈ 1 u) gives a factor of ≈ 32. This ratio is independent of unit system because it uses relative masses (dimensionless on the atomic scale).

Step-by-Step Solution:

Verification / Alternative check:

Molar masses confirm the same ratio: 32 g/mol for O2 versus 1 g per mol of H atoms (or 2 g/mol for H2). The dimensionless factor remains 32 for O2 against H.

Why Other Options Are Wrong:

12, 14, 16 confuse the atomic mass of oxygen or nitrogen with the diatomic molecular comparison; 2 would compare H2 to H, not O2 to H.

Common Pitfalls:

Mixing up atoms and molecules (e.g., comparing O atom to H atom would give 16, not 32). Always check whether the comparison is per atom or per molecule.

Final Answer:

32