Structure, Preparation, Properties and Uses of hydrogen peroxide

Concentration of H₂O₂ :

Physical properties :
Boiling point → 152º C
Melting point → −0.4º C
It is completely miscible in water.
It is stored in plastic (or) wax coated glass bottles.
Rough surface can decompose H₂O₂
H₂O₂ (Hydrogen peroxide) acts as oxidising agent and also reducing agent in both acidic and basic media.
H₂O₂ acts as a stronger oxidising agent than reducing agent due to high S.R.P value
Oxidising properties → \tt H_{2}O_{2} + [O], nascent \ oxygen
Acidic medium → \tt H_{2}O_{2} + 2H^{+} + 2e^{-} \rightarrow 2H_{2}O, E^{o} = +1.77 V
Basic medium → \tt H_{2}O_{2} + 2e^{-} \rightarrow 2OH^{-}, E^{o} = +0.87 V

With O₃

Cl₂ reacts with \tt H_{2}O_{2} \rightarrow 2HCl + O_{2}(antichlor)

Bleaching action :
\tt H_{2}O_{2} \rightarrow H_{2}O + [O] nascent \ oxygen
Its bleaching action is due to nascent [O] oxygen.
Org - matter(Veg - matter coloured) + [O] → H₂O + Colourless matter.
Its bleaching action is permanent.
SO₂ bleaches substances by reduction (Temporary action)

Structure of H₂O₂ :
Open book structure

• Hybridization sp³
• Non linear, non planar
• O — H is polar
• O — O is non polar.

Strength of H₂O₂ is expressed in terms of volume i.e 10 vol, 20 vol ----------
It is decided by the volume of O₂ liberated.
Vol of O₂ gas liberated = Vol of H₂O₂ × strength of H₂O₂ in volumes 
2 lit of 10vol H₂O₂ liberates 20 lit of O₂
5 ml of 20 vol H₂O₂ liberates 100 × 10⁻³ lit O₂

O₂ liberated = 10 × 1 = 10 L of O₂
68gr — 22.4 L of O₂
? — 10 L of O₂
x = \frac{68 \times 10}{22.4} = 30.36 \ of \ H_{2}O_{2}
= = \left\{30.36 \left(\frac{w}{v}\right) \% \right\} \ \rightarrow Perhydrol
molarity = \frac{w}{GMW \times vl}
= \frac{30.36}{34 \times 1} = 0.893 M = 0.893 × 2 = 1.786 N