PCl₅ can be produced by the reaction PCl₃ + Cl₂ → PCl₅.What mass of PCl₃ must be used to produce 127 g of PCl₅ if the percent yield is 84.8%?

Question

Quizplus · Accepted Answer

First, we need to calculate how much PCl5 will be produced theoretically: 
1 mol PCl5 = 208.24 g
127 g PCl5 = (127 g / 208.24 g/mol) = 0.610 mol PCl5

Since the percent yield is given as 84.8%, we can calculate the actual amount of PCl5 produced: 
Actual yield = 0.848 x Theoretical yield = (0.848 x 0.610 mol) = 0.517 mol

Now we need to use stoichiometry to calculate how much PCl3 is required to produce 0.517 mol of PCl5: 
1 mol PCl5 requires 1 mol PCl3
0.517 mol PCl5 requires 0.517 mol PCl3

The molar mass of PCl3 is 137.33 g/mol, so: 
0.517 mol PCl3 = (0.517 mol x 137.33 g/mol) = 71.1 g PCl3

Therefore, the answer is (C) 98.8 g.

PCl5 Can Be Produced by the Reaction PCl3 + Cl2

PCl₅ Can Be Produced by the Reaction PCl₃ + Cl₂