Excess lead (II) nitrate solution is added to 1.30 g of zinc powder and the mixture is stirred. When the reaction is finished the lead formed is filtered, dried and weighted. It has a mass of 3.31 g. What is the percentage yield of the lead?

Pb(NO3)2 + Zn -> Pb + Zn(NO3)2

A) 80
B) 90
C) 100
D) 70
E) 60

Answer is 80% moles of zn =1.30/63=0.02

0.02x207=41
3.31/41x100=80%

Well, it seems like those elements had quite the reaction! Let's crunch some numbers to find out the percentage yield of lead.

First, let's determine the theoretical yield, which is the amount of lead we should have obtained if the reaction went perfectly as planned.

The molar mass of lead (Pb) is 207.2 g/mol, so 1.30 g of zinc (Zn) would produce (1.30 g / 65.38 g/mol) = 0.01988 moles of lead.

According to the balanced equation, 1 mole of zinc (Zn) produces 1 mole of lead (Pb), so our theoretical yield is also 0.01988 moles of lead.

Next, let's calculate the actual yield, which is the mass of lead we obtained in the experiment, given as 3.31 g.

Now, to find the percentage yield, we use the formula:

Percentage Yield = (Actual Yield / Theoretical Yield) × 100%

Plugging in the values, we get:

Percentage Yield = (3.31 g / 0.01988 moles) × 100% = 166.43%

Well, well, well! It seems like we actually obtained more lead than we should have according to the theoretical calculations. But wait! We can't have a percentage yield above 100%! That would be like having a cake that grows larger after you bake it.

So, let's use some investigative skills to solve this mystery. It's possible that there was some experimental error, perhaps due to incomplete drying or some leftover impurities. Overall, the answer is a humongous clownish 166.43%, which isn't possible. So, the correct answer is none of the options provided.

Now, let's go chase down the lead and see if it's making any mischief!

To calculate the percentage yield of lead, we need to compare the actual yield to the theoretical yield.

1. Calculate the moles of zinc powder:
Mass of zinc = 1.30 g
Molar mass of zinc (Zn) = 65.38 g/mol
Number of moles of zinc = Mass of zinc / Molar mass of zinc
Number of moles of zinc = 1.30 g / 65.38 g/mol

2. Using the balanced chemical equation, we can determine the ratio of moles of zinc to moles of lead:
1 mole of Zn reacts with 1 mole of Pb

3. Theoretical yield of lead:
Number of moles of lead = Number of moles of zinc

4. Calculate the mass of lead:
Molar mass of lead (Pb) = 207.2 g/mol
Mass of lead = Number of moles of lead x Molar mass of lead

5. Calculate the percentage yield:
Percentage yield = (Actual yield / Theoretical yield) x 100
Percentage yield = (3.31 g / (Number of moles of lead x Molar mass of lead)) x 100

Now, plug in the values to calculate the percentage yield:

Number of moles of zinc = 1.30 g / 65.38 g/mol = 0.01986 mol
Number of moles of lead = Number of moles of zinc = 0.01986 mol
Mass of lead = 0.01986 mol x 207.2 g/mol = 4.11 g

Percentage yield = (3.31 g / 4.11 g) x 100 ≈ 80.537%

Therefore, the percentage yield of the lead is approximately 80%.

The correct answer is A) 80.

To find the percentage yield, we need to compare the actual yield of lead with the theoretical yield of lead.

1. Calculate the number of moles of zinc (Zn):
- Use the molar mass of zinc (atomic weight) to convert the mass of zinc powder to moles.
- The atomic weight of zinc is 65.38 g/mol.

Mass of zinc = 1.30 g
Moles of zinc = Mass of zinc / Molar mass of zinc

2. Use the stoichiometry of the balanced equation to find the number of moles of lead (Pb):
- From the balanced equation, we know that 1 mole of zinc reacts with 1 mole of lead.
- Therefore, the number of moles of lead formed is equal to the number of moles of zinc used.

3. Calculate the theoretical yield of lead:
- Multiply the number of moles of lead by the molar mass of lead (atomic weight).
- The atomic weight of lead is 207.2 g/mol.

4. Calculate the percentage yield:
- Divide the actual yield of lead by the theoretical yield and multiply by 100 to get the percentage.

Now, let's calculate the percentage yield step by step.

1. Moles of zinc:
Moles of zinc = 1.30 g / 65.38 g/mol

2. Moles of lead:
From the balanced equation, we know that 1 mole of zinc reacts with 1 mole of lead.
Therefore, Moles of lead = Moles of zinc

3. Theoretical yield of lead:
Theoretical yield = Moles of lead * molar mass of lead
Theoretical yield = Moles of lead * 207.2 g/mol

4. Percentage yield:
Percentage yield = (Actual yield / Theoretical yield) * 100
Percentage yield = (3.31 g / Theoretical yield) * 100

Now, perform the calculations and determine the correct option:

- Use the given values and calculated values to find the answer options.
- Divide the actual yield (3.31 g) by the theoretical yield and multiply by 100 to calculate the percentage yield.
- Compare the calculated percentage yield with the answer options to find the correct one.

Zn + Pb(NO3)2 ==> Pb + Zn(NO3)2

mols Zn = grams Zn/atomic mas = ?
mols Pb formed = mols Zn
grams Pb = mols Pb x atomic mass Pb. This is the theoretical yield (TY). The actual yield (AY) is given in the problem as 3.31 grams.
% yield = (AY/TY)*100 = ?