A student begins with 9.7 mL of a 0.26 M Cu(NO3)2 solution and performs copper cycle lab. She recovers 0.075 grams of copper metal.
A) What is the Theoretical Yield
B) What is the Actual Yield
C) What is the Percent Yield
To find the theoretical yield, actual yield, and percent yield, we need to follow these steps:
Step 1: Determine the balanced chemical equation for the reaction.
In this case, since the copper metal is being recovered, the balanced equation is:
Cu(NO3)2 + 2NaOH → Cu(OH)2 + 2NaNO3
Step 2: Convert the given information to moles.
- Convert the volume of the Cu(NO3)2 solution to moles:
9.7 mL × (1 L / 1000 mL) × (0.26 mol / 1 L) = 0.002522 mol
- Convert the mass of the copper metal to moles:
0.075 g × (1 mol / 63.55 g) = 0.001179 mol
Step 3: Determine the stoichiometry relationship between the reactant and the product.
From the balanced equation, we see that 1 mole of Cu(NO3)2 reacts with 1 mole of Cu(OH)2. Thus, the stoichiometry relationship between Cu(NO3)2 and Cu is 1:1.
Step 4: Calculate the theoretical yield.
Since the stoichiometry relationship between Cu(NO3)2 and Cu is 1:1, the theoretical yield of Cu is the same as the moles of Cu(NO3)2 used:
Theoretical Yield = 0.002522 mol
Step 5: Calculate the actual yield.
The actual yield is given as 0.075 grams of copper metal.
Step 6: Calculate the percent yield.
Percent Yield = (Actual Yield / Theoretical Yield) × 100
Now, let's calculate each value:
A) Theoretical Yield = 0.002522 mol
B) Actual Yield = 0.075 grams
C) Percent Yield = (0.075 g / 0.002522 mol) × 100 = 2973.85%
Note: Percent yield can be over 100% if the actual yield is greater than the theoretical yield.