Answer to Question #329264 in General Chemistry for Easy

Question

Calculate the percent yield for the reaction: P4 (s) + 6 Cl2 (g) → 4 PCl3 (l) if 75.0 g of phosphorus reacts with excess chlorine gas to produce 111.0 g of phosphorus trichloride.

Answer 1

P_{4 (s)} + 6 Cl_{2 (g)} → 4 PCl_{3 (l)}

According to the reaction, n (PCl₃) = 4 x n (P₄).

n = m / M

M (P₄) = 123.9 g/mol

M (PCl₃) = 137.3 g/mol

n (P₄) = 75/123.9 = 0.61 mol

n (PCl₃) = 4 x n (P₄) = 4 x 0.61 = 2.4 mol

m (PCl₃)_theoretical = n x M = 2.4 x 137.3 = 332.4 g

%(PCl₃) = 111 / 332.4 x 100 = 33.4%