A 0.1818 g sample of sodium oxalate required 28.12 ml of a potassium permanganate solution to reach the endpoint (assume the reaction was carried out in excess acid). A 5.000 g sample of tin (II) sulfate containing potassium sulfate as an impurity was found to require 35.00 ml of the above permanganate solution (in excess acid) to reach the endpoint. What was the percentage of tin in the sample?
I don't have any clue how to do this, help?
1. Write and balance the equation for oxalate and permananate, then calculate the M of the permanganate.
2. Write and balance the equation for the Sn and permanganate.
3. mols MnO4^- = M x L = ?
Convert mols MnO4^- to mols Sn using the coefficients in the balanced equation. grams Sn = mols Sn x atomic mass Sn.
4. %Sn = (mass Sn/mass sample)*100 = ?
Post your work if you have trouble and I can help you through it.
5CrO42-+2MnO4-+16H+->2MN2++8H2O+10CO2
.1818gC2O4*1mol/88.019gNaC2O4*2molMnO4-/5molC2O42-=8.2618^-4mol/.02812l=.02938M
(Was I supposed to use the molar mass of NaCrO4 or just CrO4 for this step?)
2)16H++5Sn2++2MnO4- -->5Sn4++2Mn2++8H2O
.02938M*.035L=.001028mol MnO4-
.001028molMnO4-*5molSn2+/2molMnO4-*118.71gSn=.3052gSn
.3052gSn/5gSn*100=6.104%
Thank you for your help.
To find the percentage of tin in the sample, you will need to use the concept of molar ratios.
1. Calculate the number of moles of sodium oxalate:
- The molar mass of sodium oxalate (Na2C2O4) is 134.00 g/mol.
- Use the formula: moles = mass / molar mass.
- The mass of the sodium oxalate is given as 0.1818 g.
moles of sodium oxalate = 0.1818 g / 134.00 g/mol
2. Calculate the number of moles of permanganate used in the sodium oxalate reaction:
- The balanced chemical equation for the reaction between sodium oxalate and potassium permanganate is:
5Na2C2O4 + 2KMnO4 + 8H2SO4 → 10CO2 + 2MnSO4 + K2SO4 + 8H2O + 10Na2SO4
- The stoichiometric ratio between sodium oxalate and permanganate is 5:2.
moles of permanganate = (moles of sodium oxalate) * (2 moles of permanganate / 5 moles of sodium oxalate)
3. Calculate the number of moles of permanganate used in the tin (II) sulfate reaction:
- The balanced chemical equation for the reaction between tin (II) sulfate and potassium permanganate is:
SnSO4 + 2KMnO4 + 4H2SO4 → Sn(SO4)2 + 2MnSO4 + K2SO4 + 4H2O
- The stoichiometric ratio between tin (II) sulfate and permanganate is 1:2.
moles of permanganate in tin (II) sulfate reaction = (moles of permanganate in sodium oxalate reaction) * (2 moles of permanganate / 2 moles of tin (II) sulfate)
4. Calculate the number of moles of tin in the sample:
- The balanced chemical equation for the reaction between tin (II) sulfate and potassium permanganate is:
SnSO4 + 2KMnO4 + 4H2SO4 → Sn(SO4)2 + 2MnSO4 + K2SO4 + 4H2O
- The stoichiometric ratio between tin (II) sulfate and tin is 1:1.
moles of tin = moles of permanganate in tin (II) sulfate reaction
5. Calculate the molar mass of tin:
- The molar mass of tin (Sn) is 118.71 g/mol.
6. Calculate the mass of tin in the sample:
- Use the formula: mass = moles * molar mass.
- The moles of tin were calculated in step 4.
mass of tin = moles of tin * molar mass of tin
7. Calculate the percentage of tin in the sample:
- Use the formula: percentage = (mass of tin / total mass of the sample) * 100.
- The total mass of the sample is given as 5.000 g.
percentage of tin in the sample = (mass of tin / 5.000 g) * 100
Follow these steps with the given values to find the percentage of tin in the sample.
To find the percentage of tin in the sample, we need to use the concept of stoichiometry and the balanced chemical equation of the reaction. Let's break down the steps to solve this problem:
Step 1: Determine the mole ratio between sodium oxalate and potassium permanganate.
First, we need to calculate the number of moles of sodium oxalate used in the reaction. To do this, we can use the molar mass of sodium oxalate (Na2C2O4). It is 133.999 g/mol
We know that the sample of sodium oxalate used weighs 0.1818 g, so we can calculate the number of moles using the formula:
moles of sodium oxalate = (mass of sample) / (molar mass)
Step 2: Determine the molarity of the potassium permanganate solution.
To determine the molarity (M) of the potassium permanganate solution, we need to divide the moles of potassium permanganate used by the volume of the solution used (in liters).
The volume of potassium permanganate solution used is given as 28.12 mL, which is equal to 0.02812 L.
The number of moles can be calculated using the formula:
moles of potassium permanganate = Molarity * Volume (L)
Step 3: Determine the mole ratio between tin (II) sulfate and potassium permanganate.
Now, we will use the balanced chemical equation to determine the mole ratio between tin (II) sulfate and potassium permanganate.
The balanced chemical equation is:
5 Na2C2O4 + 2 KMnO4 + 8 H2SO4 → 8 H2O + 2 MnSO4 + 10 CO2 + K2SO4 + 10 Na2SO4
From this equation, we can see that the mole ratio of tin (II) sulfate to potassium permanganate is 5:2.
Step 4: Determine the moles of tin (II) sulfate.
We can calculate the moles of tin (II) sulfate using the mole ratio of tin (II) sulfate to potassium permanganate. We already know the moles of potassium permanganate from Step 2.
moles of tin (II) sulfate = (moles of potassium permanganate) * (mole ratio)
Step 5: Calculate the weight of tin in the sample.
To calculate the weight of tin in the sample, we can use the moles of tin (II) sulfate we calculated in Step 4 and the molar mass of tin (II) sulfate. Its molar mass is 310.84 g/mol.
weight of tin = (moles of tin (II) sulfate) * (molar mass of tin (II) sulfate)
Step 6: Calculate the percentage of tin in the sample.
Finally, we can determine the percentage of tin in the sample by dividing the weight of tin (calculated in Step 5) by the initial weight of the sample (5.000 g) and multiplying by 100.
percentage of tin = (weight of tin / initial weight of sample) * 100
By following these steps, you should be able to solve the problem and find the percentage of tin in the sample.