Answer:
Percent yield = 69.4%
Explanation:
Given data:
Percent yield = ?
Actual yield of copper = 4.65 g
Mass of aluminium = 1.87 g
Mass of copper sulfate = excess
Solution:
Chemical equation:
2Al + 3CuSO₄ → Al₂(SO₄)₃ + 3Cu
Number of moles of Aluminium:
Number of moles = mass/ molar mass
Number of moles = 1.87 g/27 g/mol
Number of moles = 0.07 mol
Now we will compare the moles of Al with copper.
Al : Cu
2 : 3
0.07 : 3/2×0.07 =0.105 mol
Mass of Copper:(Theoretical yield)
Mass = Number of moles × molar mass
Mass = 0.105 mol × 63.5 g/mol
Mass = 6.7 g
Percent yield:
Percent yield = Actual yield / theoretical yield × 100
Percent yield = 4.65 g/ 6.7 g × 100
Percent yield = 69.4%
