Tetraphosphorus trisulfide, P₄S₃, is used in the manufacture of “strike anywhere” matches. Elemental phosphorus and sulfur react directly to form P₄S₃:

If we have 153 g of S₈ and an excess of phosphorus, what mass of P₄S₃ can be produced by this reaction?

Strategy The heart of any stoichiometry problem is the balanced chemical equation that provides the mole ratio we need. We must convert between masses and the number of moles in order to use this ratio, first for the reactant, S₈, and at the end of the problem for the product, P₄S₃. Molar masses provide the needed conversion factors. The phrase “excess of phosphorus” tells us that we have more than enough P₄ to consume 153 g of S₈ completely.

Transcribed Image Text:

8 P4+3 Sg 8 P4S3