If 62.4 grams of white phosphorus react with 136.2 grams of chlorine, how many grams of phosphorus trichloride can be formed?

P4 + 6Cl2 yields 4PCl3

The balanced chemical reaction is given to be,

P4 + 6Cl2 - - > 4PCl3

The masses of the involved chemicals are calculated below.

P4 = (4) (30.97 g/mol) = 123.88 g

6Cl2 = (6) (35.45g/mol) (2) = 425.4 g

4PCl3 = (4) (30.97 + 3x35.45) = 549.28 g

With the given masses from this item, we solve for the mass of PCl3 by ratio and proportion.

62.4 g P x (549.28 g PCl3 / 123.88 g P) = 276.679 g PCl3

136.2 g Cl x (549.28 g PCl3 / 425.4 g Cl) = 175.86 g PCl3

Since, lesser PCl3 is produced from the 136.2 g of Cl then Cl is the limiting reactant and the answer is 175.86 g of PCl3.