A solution of hydrogen peroxide, H2O2, is titrated with a solution of potassium permanganate, KMnO4.

It requires 51.7 mL of 0.145 M KMnO4 to titrate 20.0 g of the solution of hydrogen peroxide. What is the mass percentage of H2O2 in the solution?

If you want the whole equation I'll type it but it's long. I think all you need is the mole ratio which is 5 mol H202 : 2 mol KMnO4.

so far I changed 51.7 mL to L. Got .00750 mol KMnO4 using molarity and volume. converted that to .0188 mol H2O2.

You may have almost finished it then but I'll start from the beginning.

Convert M x L KMnO4 to mols.
Convert mols KMnO4 to mols H2O2 using the coefficients in the balanced equation.
Convert mols H2O2 to grams H2O2.
Then %H2O2 = [grams H2O2/mass of sample]*100.
Mass of the sample is 20.0 g in the problem.

Well, it seems like you've done quite a bit of work already! Kudos to you! Now let's calculate the mass percentage of H2O2 in the solution.

To find the mass percentage of H2O2, we need to determine the mass of H2O2 in the solution and divide it by the total mass of the solution, then multiply by 100%.

First, let's calculate the molar mass of H2O2:

2(1.01 g/mol of H) + 2(16.00 g/mol of O) = 34.02 g/mol of H2O2

Next, we can use the mole ratio you provided (5 mol H2O2 : 2 mol KMnO4) to figure out how many moles of H2O2 were in the 0.00750 mol of KMnO4:

0.00750 mol KMnO4 x (5 mol H2O2 / 2 mol KMnO4) = 0.0188 mol H2O2

Since you mentioned that 20.0 g of the solution of hydrogen peroxide was titrated, we can assume that the 0.0188 mol of H2O2 is present in 20.0 g of solution. Now we can calculate the mass percentage of H2O2:

Mass of H2O2 = 0.0188 mol x 34.02 g/mol = 0.638 g

Mass percentage of H2O2 = (mass of H2O2 / total mass of solution) x 100%
= (0.638 g / 20.0 g) x 100%
= 3.19%

Therefore, the mass percentage of H2O2 in the solution is approximately 3.19%. Just a heads up, please double-check all the calculations and units to ensure accuracy.

To find the mass percentage of H2O2 in the solution, we need to calculate the mass of H2O2 and divide it by the total mass of the solution. Here's how:

1. Calculate the molar mass of H2O2:
H2O2 = (2 x 1.008 g/mol) + (2 x 15.999 g/mol)
= 34.014 g/mol

2. Calculate the moles of H2O2 in 51.7 mL (0.0517 L) of 0.145 M KMnO4 solution:
Moles of KMnO4 = concentration (M) x volume (L)
= 0.145 M x 0.0517 L
= 0.0075185 mol KMnO4

According to the mole ratio of 5 moles H2O2 to 2 moles KMnO4, we can determine the moles of H2O2:
Moles of H2O2 = (5/2) x 0.0075185 mol KMnO4
= 0.01879625 mol H2O2 (rounded to 0.0188 mol)

3. Calculate the mass of H2O2 in the solution:
Mass of H2O2 = Moles of H2O2 x Molar mass of H2O2
= 0.0188 mol x 34.014 g/mol
= 0.6390432 g (rounded to 0.639 g)

4. Calculate the mass percentage of H2O2 in the solution:
Mass percentage = (Mass of H2O2 / Total mass of solution) x 100
= (0.639 g / 20.0 g) x 100
= 3.195% (rounded to 3.20%)

Therefore, the mass percentage of H2O2 in the solution is approximately 3.20%.

To find the mass percentage of H2O2 in the solution, we first need to calculate the number of moles of H2O2 in the given sample.

Given:
- Volume of KMnO4 solution used = 51.7 mL = 0.0517 L
- Molarity of KMnO4 solution = 0.145 M
- Mole ratio of H2O2 to KMnO4 = 5 mol H2O2 : 2 mol KMnO4
- Mass of the H2O2 solution = 20.0 g

Step 1: Calculate the number of moles of KMnO4 solution used:
Moles of KMnO4 = Molarity x Volume = 0.145 M x 0.0517 L = 0.00750 mol KMnO4

Step 2: Calculate the number of moles of H2O2 using the mole ratio:
Moles of H2O2 = (5/2) x Moles of KMnO4 = (5/2) x 0.00750 mol KMnO4 = 0.0188 mol H2O2

Step 3: Calculate the mass of H2O2 in the sample:
Mass of H2O2 = Moles of H2O2 x Molar mass of H2O2
Molar mass of H2O2 = 2(1.01) + 2(16.00) = 34.02 g/mol (2 hydrogens + 2 oxygens)
Mass of H2O2 = 0.0188 mol H2O2 x 34.02 g/mol = 0.638 g H2O2

Step 4: Calculate the mass percentage of H2O2 in the solution:
Mass percentage of H2O2 = (Mass of H2O2 / Mass of the solution) x 100%
Mass of the solution = Mass of H2O2 + Mass of solvent
Assuming the solvent is water, the mass of the solvent is approximately equal to the mass of the solution.
Mass of the solution = Mass of H2O2 + 20.0 g (given)
Mass percentage of H2O2 = (0.638 g H2O2 / (0.638 g H2O2 + 20.0 g)) x 100% = 3.09%

Therefore, the mass percentage of H2O2 in the solution is approximately 3.09%.