Answer:
Percent yield = 22.8 %
Explanation:
Step 1: Data given
Numbers of moles copper = 0.0970 moles
Mass of copper(I) sulfide = 1.76 grams
Step 2: The balanced equation
2Cu + S ⇒ Cu2S
Step 3: Calculate moles of Cu2S
For 2 moles Cu we need 1 mol S to produce 1 mol Cu2S
For 0.0970 moles Cu we'll hace 0.0970 / 2 = 0.0485 moles
Step 4: Calculate mass of Cu2S
Mass Cu2s = moles Cu2S * molar mass Cu2S
Mass Cu2S = 0.0485 moles * 159.16 g/mol
Mass Cu2S = 7.72 grams
Step 5: Calculate percent yield
Percent yield = (actual yield/ theoretical mass) * 100%
Percent yield = (1.76 grams / 7.72 grams)*100%
Percent yield = 22.8 %