Question

0.2 of sample H2O2 reduced 20 ml of 0.1 M KMnO4 solution in acidic medium. What is the percentage purity of H2O2?

Solution

Correct option is

85

 

No. of moles of KMnO4 present in 20 ml of 0.1 M KMnO4 solution   

The balanced equation for the redox reaction is:

                                                                                  

From the equation,

2 moles of KMnO4 ≡ 5 moles of H2O2

                                                           

Mol. Wt. of H2O2 = 34

∴ Amount of H2O2 actually present = 34 × 5 × 10–3 = 0.17 g

.

SIMILAR QUESTIONS

Q1

In which of the following reaction, oxidation number of N remains unchanged?

Q2

 

KMnO4 acts as a strong oxidizing agent in acidic medium. The reaction that occurs is

What will be the effect on the electrode potential of a half-cell represented as  if the concentration of H+ ion is doubled in solution?

Q3

In which of the following oxidation state of phosphours is + 3?

Q4

Determine the volume of M/8 KmnO4 solution required to react completely with 25.0 cm3 of M/4 FeSO4 solution is acidic medium.

Q5

Calculate the concentration of hypo (Na2S2O3.5H­2O) solution in g dm–3 if 10.0 of this solution decolourised 15 mL of M/40 iodine solution.

Q6

0.5 g of an impure sample of oxalate was dissolved in water and the solution made to 100 ml. On titration 10 ml of this solution required 15 ml of N/20 KMnO4 solution. Calculate the percentage of pure oxalate in the sample.

Q7

Predict whether zinc and silver react with 1 M sulphuric acid to give out hydrogen or not. Give that the standard potentials of zinc and silver are – 0.76 volt and +0.80 volt respectively.

Q8

 

Can a solution of 1 M copper sulphate be stored in a vessel made of nickel metal? Given that

.

or Is it possible to store copper soulphate solution in a nickel vessel?

Q9

16.6 g of pure potassium iodide was dissolved in water and the solution was made up to one litre. V cm3 of this solution was acidified with 20 cm3of 2 M HCl. The resulting solution required 10 cm3 of decinormal KIO3for complete oxidation of I ions to ICl. Find out the value of V.

Q10

Both  (aq) can be used to titrate Fe2+ (aq). If in a given titratoion, 24.50 cm3 of 0.1 M  were used, then what volume of 0.1 M  solution would have been used for the same titration?