Determining Volume Strength of Hydrogen Peroxide Solution

[clarewillow]

Determintion of the volume strength of the solution of hydrogen peroxide provided...

Homework Statement

Hi, I have to dertermine the volume strength of the solution of hydrogen peroxide provided. NOTE the volume strength as I'm not quite sure how to get this!

I had to dilute 10ml, accurately measured, of the hydrogen peroxide to 100ml with distilled water using a volumetric flask. To 10ml of the dilution, 20ml bench sulphuric acid was added and then titrated with 0.02M potassium permanganate solution.

My results where: Titration 1 : 10.6ml
Titration 2 : 10.5ml

The equation for the reaction is :

2KMnO₄ + 3H₂SO₄ + 5H₂O₂ ====> K₂SO₄ + 2MnSO₄ + 8H₂0 + 5O₂

The molecular mass of hydrogen peroxide is 34.016

I really am stuck. I have been trying to work it out from 2 this afternoon, and now i can't even see straight If anyone can please guide me through i would be extremely grateful.

Thank you in advance

Homework Equations

The Attempt at a Solution

 

[Borek]

Please try to be more specific, as it is not clear what is your problem. Do you know how to calculate number of moles of hydrogen peroxide in your sample? Do you know what is the definition of "volume strength"?

 

[clarewillow]

Hi, yes i pretty much need to know how to work out the molarity. And then i do believe i need to work out how to convert this to volume strength. Thanks for your time x

 

[chemisttree]

You still didn't answer Borek's question. Do you know how to calculate moles of hydrogen peroxide in the sample you titrated?

Hint: for every 2 moles of permanganate, you neutralize 5 moles of hydrogen peroxide.

 

[ghosty]

knowing that the mole ratio is 2:5 doesn't change anything the real question here is what is volume strength
i think volume strenght is = factor x titre x nominal x gas present.

 

[Borek]

volume strenght is = factor x titre x nominal x gas present.

I am doing my best to understand what you mean and I fail. What is "gas present", what is "factor" - as long as you don't define terms used, your definition is useless.

Volume strength is the ratio of the volume of oxygen gas liberated to the volume of H₂O₂ solution used.