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**Calculation of Volume Strength of Hydrogen Peroxide**

In this chapter, you can expect questions where you have to carry out calculations on volume strength of hydrogen peroxide. Hydrogen peroxide forms a hydrate when mixed in water. When solving questions related to strength of hydrogen peroxide, remember these points:

- 'X' volume of 'Y%' hydrogen peroxide means that 1 millilitre of the solution will give 'X' mL of oxygen at STP. 1 litre solution will give 10 litre of oxygen. 1 ml solution will give 10 mL of oxygen.
- Here's the chemical equation behind this decomposition: $2H_{2}O_{2}→2H_{2}O+O_{2}$. According to this, 1 mole of $O_{2}$ = 2 moles of $H_{2}O_{2}$
- At STP, one mole of oxygen occupies 22.7 litres.
*Shortcut for molarity:*If molarity of a $H_{2}O_{2}$ solution is M, then its volume strength will be 11.2 X M.*Shortcut for normality:*If normality of a $H_{2}O_{2}$ solution is N, then its volume strength will be 5.6 X N.

**Here's a question you can solve:**