Answer:
78.8%
Explanation:
The equation of the reaction is;
2 Al(s) + Fe2O3(aq) ------> Al2O3(aq) + 2Fe(s)
Number of moles in 20g of Al= 20g/27 g/mol = 0.74 moles
From the reaction equation;
2 moles of Al yields 2 moles of Fe
0.74 moles of Al yields 0.74 moles of Fe
Hence;
Mass of Fe produced = 0.74 moles of Fe * 56 g/mol
Mass of Fe produced = 41.44 g of Fe (This is the theoretical yield of Fe)
percent yield = actual yield/ theoretical yield * 100
actual yield = 32.67 grams of iron
percent yield = 32.67 g/41.44 g * 100
percent yield = 78.8%
