Question

A student wants to reclaim the iron from an 18.0 gram sample of iron (III) oxide, which occurs according to the reaction below: how many grams of iron can be reclaimed.

Answer 1

12.6 g

Step-by-step explanation:

Step 1: Write the balanced decomposition reaction

2 Fe₂O₃ ⇒ 4 Fe + 3 O₂

Step 2: Calculate the moles corresponding to 18.0 g of Fe₂O₃

The molar mass of Fe₂O₃ is 159.69 g/mol.

18.0 g × 1 mol/159.69 g = 0.113 mol

Step 3: Calculate the moles of Fe formed from 0.113 moles of Fe₂O₃

The molar ratio of Fe₂O₃ to Fe is 2:4. The moles of Fe formed are 4/2 × 0.113 mol = 0.226 mol

Step 4: Calculate the mass corresponding to 0.226 moles of Fe

The molar mass of Fe is 55.85 g/mol.

0.226 mol × 55.85 g/mol = 12.6 g