P4O10 + 6PCl5 → 10POCl3
To calculate how many grams POCl3 will be formed from
5.0 g PCl5, you need

A) to know if the product is a gas.
B) to know whether either reactant is a gas.
C) information about the mass of P4O10 reacting.
D) information about the temperature and pressure at which the reaction occurs.