Given the following reactions:
Fe + Br₂ → FeBr₂
3 FeBr₂ + Br₂ → Fe₃Br₈
If each reaction is 82.0% efficient,what mass of iron is necessary to make 8.45 g of Fe₃Br₈?

Question

Quizplus · Accepted Answer

First, we need to find the theoretical yield of Fe₃Br₈ using the given reactions and mass of product: 8.45 g Fe₃Br₈ x (1 mol / 312.61 g) x (3 mol / 1 mol) x (1 mol / 465.76 g) x (1 mol / 1 mol) = 0.00516 mol Fe Then, we can use the stoichiometry of the first reaction to find the mass of iron needed: 0.00516 mol Fe x (1 mol / 1 mol) x (1 mol / 82.0%) x (55.85 g / 1 mol) = 2.61 g Fe Therefore, the best choice is E.

Given the Following Reactions