The grams of Fe₂O₃ that are formed is 47.68 g
calculation
Step 1: write the equation for reaction
4 Fe +3O₂ → 2 Fe₂O₃
Step 2: find the moles of Fe
moles = mass÷ molar mass
= 33.4 g÷55.8 g/mol =0.5986 moles
Step 3 : use the mole ratio to determine the moles of Fe₂O₃
That is from equation above Fe:Fe₂O₃ is 4:2 therefore the moles of Fe₂O₃ is = 0.5986 moles x 2/4 =0.2993 moles
Step 4 : find the mass of Fe₂O₃
mass = mass x molar mass
The molar mass of Fe₂O₃ = (55.8 x 2 +(15.9 x3) = 159.3 g/mol
mass is therefore = 0.2993 moles x 159.3 g/mol =47.68 g
