Benzoyl Peroxide

What is Benzoyl Peroxide?

Benzoyl peroxide is an organic compound which has the chemical formula C₁₄H₁₀O₄.

It can be prepared from the reaction between benzoyl chloride and hydrogen peroxide. The compound consists of two benzoyl groups that are linked by a peroxide group. Benzoyl peroxide is known to have antibacterial properties and is widely used in the treatment of acne.

Benzoyl Peroxide Structure

The structure of a benzoyl peroxide molecule is illustrated below.

From the illustration provided above, it can be observed that the peroxide group consisting of a single bond between two oxygen atoms links the two benzoyl groups. Therefore, the chemical formula of benzoyl peroxide can also be written as (C₆H₅CO)₂O₂.

Due to the weak nature of the oxygen-oxygen bond in the peroxide group that connects the two C₆H₅CO groups, benzoyl peroxide tends to undergo homolytic fission and form two separate free radical species. The chemical equation for this reaction is provided below.

(C₆H₅CO)₂O₂ → 2C₆H₅CO₂^•

These free radical species have a very reactive nature due to the presence of an unpaired electron. The formation of these radicals via the homolysis of benzoyl peroxide is encouraged by an increase in temperature.

Table of Contents

• Properties of Benzoyl Peroxide
• Physical Properties
• Chemical Properties
• Uses of Benzoyl Peroxide
• Frequently Asked Questions – FAQs

Properties of Benzoyl Peroxide

The physical and chemical properties of benzoyl peroxide are discussed in this subsection.

Chemical Data of Benzoyl Peroxide

Physical Properties of Benzoyl Peroxide

• Benzoyl peroxide exists as a colourless solid which has a crystalline structure.
• It has a faint odour which resembles the smell of benzaldehyde.
• C₁₄H₁₀O₄ is insoluble in water, somewhat soluble in alcohols, and quite soluble in ethers and chloroform.
• Solid benzoyl peroxide is very volatile and dangerous, especially when dry. It is highly reactive and tends to spontaneously explode.
• At temperatures approaching 103^oC, this compound decomposes.

Chemical Properties of Benzoyl Peroxide

• C₁₄H₁₀O₄ is an explosive, flammable chemical.
• It is also regarded as an irritant since it can even cause swelling of the skin.
• Benzoyl peroxide can be prepared via the treatment of benzoyl chloride with barium peroxide.
• This compound readily undergoes homolytic fission to yield free radical products that are highly reactive.
• Upon contact with human skin, it breaks down to yield benzoic acid and oxygen.

Uses of Benzoyl Peroxide

Benzoyl peroxide is a very important organic peroxide due to its wide range of applications. It is also produced on a large scale industrially. Some of the uses of this compound are listed in this subsection.

• In concentrations between 2.5% to 10%, this compound can be applied on human skin to treat acne.
• Benzoyl peroxide can be used to remove dye stains and ink from many playthings such as vinyl dolls.
• It can also be used as a bleaching agent in cheese and bread.
• This compound is used in tooth whitening processes and also in cosmetic hair colouring.
• In the field of organic chemistry, benzoyl peroxide is a very convenient oxidant.
• The polymerization process of resins can be initiated with the help of this compound.
• It is also used as a catalyst in the synthesis of thermosetting polyester resins.

Thus, the structure, properties, and uses of benzoyl peroxide are briefly discussed in this article. To learn more about this compound and other peroxides, such as hydrogen peroxide, register with BYJU’S and download the mobile application on your smartphone.