Chapter 4 Stoichiometry: Quantitative Information about Chemical Reactions - 4-2 Reactions in Which One Reactant Is Present in Limited Supply - Review & Check for Section 4-2 - Page 147: 1

B

Methanol: $32.05\ g/mol$ Oxygen: $32.00\ g/mol$ Since they have practically the same molecular weight and the same mass, the limiting reactant is oxygen, because it has a bigger stoichiometric coefficient (3 vs. 2 from methanol).