Volume strength of Hydrogen Peroxide - Definition, formula, practice problems & FAQs

Which chemical is the best bleaching agent for cotton fabrics, how their concentration is represented for commercial purposes, their dilute/varying concentration solution be used for various applications?

Hydrogen peroxide (H₂O₂) is the best bleaching agent for cellulosic material and for commercial purposes thor concentration is expressed as volume strength, w/v, etc. also, dilute solution of Hydrogen peroxide (H₂O₂) with different concentrations can be used for different applications like antiseptic, disinfectants, etc.

Table of contents

Volume strength of hydrogen peroxide
Derivation of formula of mathematical form of volume strength of H₂O₂
n-factor of H₂O₂
Practice problems
Frequently asked questions-FAQs

Volume strength of hydrogen peroxide (H₂O₂)

Volume strength of H₂O₂ is represented as 30 V, 35 V, 20 V etc.

If a sample of H₂O₂ represented as 30 V H₂O₂ means one litre of this sample of H₂O₂ on decomposition gives 30 litre of O₂ gas at S.T.P.

Derivation of formula of mathematical form of volume strength of H₂O₂

The balanced chemical reaction of decomposition of H₂O₂ can be represented as

(follows first order kinetics)

Molar mass of H₂O₂ = 34 g mol^-1

According to given reaction,

we can say 1 mole of H₂O₂ produce 0.5 mole of O₂

Means, 34 g H₂O₂ produce mole of O₂

We know that 1 mole of any gas at STP occupies 22.7 L

Volume of mole of O₂ atSTP = 11.3 L

34 g H₂O₂ produce mole of O₂ at STP

34 g H₂O₂ produce 11.3 L of O₂ atSTP

To produce, 11.3 L of O₂ decomposition of 34 g H₂O₂ must be required

By definition number of equivalent of solute per litre of solution is known as normality of solution.

n - factor of H2O₂

n - factor = 2 | 0 - (-1) = 2

Practice problems

Q1. A sample of H₂O₂ solution is labelled as 30.5 V. Calculate its strength of solution?

A. 92.65 g L^-1
B. 30.5 g L^-1
C. 11.2 g L^-1
D. 87.89 g L^-1

Answer: (A)

Solution: we know, Normality =

Normality = N=5.45 N

Strength of solution (g L^-1) = normality equivalent mass =

Q2. The volume strength of a sample of H₂O₂ is ‘17 vol’. The mass of H₂O₂ present in 100 ml of this solution is

A. 0.67 g
B. 5.17 g
C. 9.7 g
D. 10.8 g

Answer: (B)

Q3. 100 mL of 2 N H₂O₂ and 150 mL of 20.5 V H₂O₂ solution are mixed then find the resulted normality of the solution?

A. 2.1 N
B. 3 N
C. 2.5 N
D. 1.9 N

Answer: (D)

Solution: volume of first solution = 100 mL

Normality of first solution = 2 N

volume of second solution = 150 mL

Volume strength of solution = 20.5 V

Q4. 20 V of H₂O2 after acidification required 20 mL of 1.2 N K₂CrO₇ for complete oxidation. The volume required of H₂O₂ solution is

A. 10 mL
B. 6.72 N
C. 5.6 N
D. 11.2 N

Answer: (B)

Frequently asked questions-FAQs

Question 1. What is the commercial name of H₂O₂ as an antiseptic?
Answer: H₂O₂ as an antiseptic sold as the name of perhydrol.

Question 2. What is the structure of H₂O₂ in gas and solid phase?
Answer: H₂O₂ has open book structure and their dihedral angle is different in both phase

Question 3. Write some use of H₂O₂
Answer: H₂O₂ used as hair bleach, antiseptic, bleaching agent etc. Hydrogen peroxide is used to disinfect tools, bleach hair, and clean surfaces. It's also used in oral care and gardening. It may be discomforting to know that a touted skin treatment can also be used as a household cleaner

Question 4. Industrially H₂O₂ purchased in bulked quantity, So, what precaution should be taken for storage of H₂O₂?
Answer: Presence of metal or traces of metal can accelerate the decomposition of H₂O₂ so H₂O₂ stored in a vessel of plastic or vessel coated with wax. Urea used as a stabilizer for storage of H₂O₂.