a student conducts and experiment by reacting 39.6g CuSO4 with an excess of MgS. The reaction yields 9.5599g CuS. What is the percentage yield? MgS+CuSO4=CuS+MgSO4
mols CuSO4 = grams/molar mass = ?
Convert mols CuSO4 to mols MgS using the coefficients in the balanced equation.
Convert mols MgS to grams. g = mols x molar mass. This is the theoretical yield(TY). The actual yield (YD) in the problem is 9.5599 g.
Then %yield = (AY/TY)*100 = ?
To calculate the percentage yield of a reaction, you need to compare the actual yield (the amount of product obtained) to the theoretical yield (the amount of product that should have been obtained according to stoichiometry). The percentage yield can be calculated using the following formula:
Percentage Yield = (Actual Yield / Theoretical Yield) × 100
In this case, we are given the mass of CuS obtained (9.5599g). To find the theoretical yield, we need to determine the stoichiometry of the reaction.
From the balanced equation: MgS + CuSO4 → CuS + MgSO4
We can see that the molar ratio between CuS and CuSO4 is 1:1. This means that for every 1 mole of CuSO4, 1 mole of CuS should be produced.
To find the number of moles of CuS, we can use the following formula:
Number of Moles = Mass / Molar Mass
Molar mass of CuS = 63.55g/mol (from the atomic masses of copper and sulfur)
Number of Moles of CuS = 9.5599g / 63.55g/mol = 0.1505 mol
Since the stoichiometry of the reaction tells us that 1 mole of CuS should be produced for every 1 mole of CuSO4, the theoretical yield of CuS is also 0.1505 mol.
To convert the theoretical yield from moles to grams, we can use the formula:
Theoretical Yield (g) = Theoretical Yield (mol) × Molar Mass
The molar mass of CuS is 63.55g/mol.
Theoretical Yield (g) = 0.1505 mol × 63.55g/mol = 9.5599g
Now that we have both the actual yield (9.5599g) and the theoretical yield (9.5599g), we can calculate the percentage yield:
Percentage Yield = (Actual Yield / Theoretical Yield) × 100
= (9.5599g / 9.5599g) × 100
= 100%
Therefore, the percentage yield of the reaction is 100%, indicating that the student obtained the maximum amount of CuS possible based on the given reactants.