Question

If a 12.39 g sample of phosphorus reacts with 42.54 g of chlorine to form only phosphorus trichloride (PCl₃), what mass of PCl₃ is formed?

a) 30.15 g
b) 54.93 g
c) 140.01 g
d) 79.71 g
e) 91.86 g

Answer 1

The mass of phosphorus trichloride formed is 54.93 g, which is found by adding the mass of phosphorus (12.39 g) and the mass of chlorine (42.54 g) together.

Step-by-step explanation:

To find the mass of phosphorus trichloride (PCl₃) formed from the given reactants, we can use the law of conservation of mass which states that the mass of the reactants in a chemical reaction must equal the mass of the products. Since all the phosphorus and chlorine react to only form phosphorus trichloride, we can add the masses of the reactants to find the mass of the product:

Mass of P + Mass of Cl₂ = Mass of PCl₃

12.39 g + 42.54 g = 54.93 g of PCl₃

Therefore, the correct answer is (b) 54.93 g of phosphorus trichloride.