The key difference between benzoyl peroxide and salicylic acid is that benzoyl peroxide belongs to the peroxide family whereas salicylic acid belongs to the carboxylic acid family.
There are many organic molecules with useful properties to humans. Benzoyl peroxide and salicylic acid are two chemicals that are largely used to treat acne. Both are good agents for fighting acne, but depending on the skin type, the reactions may vary.
What is Benzoyl Peroxide?
Benzoyl peroxide is an organic molecule with the peroxide linkage. It has two benzoyl group connected by a peroxide linkage. Its molecular formula is [C6H5C(O)]2O2. The structure of this molecule is as follows.
Benzoyl peroxide is a colorless solid, and the molar mass is 242.23 g mol−1. It may mildly dissolve in water, but readily dissolves in organic solvents. Benzoyl peroxide can be prepared by treating hydrogen peroxide with benzoyl chloride or treating benzoyl chloride with barium peroxide.
Benzoyl peroxide is useful in medicine, especially as an acne treatment. When it is in contact with the skin, it breaks down into benzoic acid and oxygen. Benzoyl peroxide is not toxic. It can also be used as a radical initiator in polymerization reactions. As any other peroxide, this also has bleaching properties. It is used in hair dyeing, teeth whitening materials etc. Further it can be used as an antiseptic.
What is Salicylic Acid?
Salicylic acid is the common name used to address monohydroxybenzoic acid. It is an aromatic compound where a carboxylic group is attached to a phenol. Rhw OH group is at the ortho position to the carboxyl group. In IUPAC nomenclature, it is named as 2-hydroxybenzenecarboxylic acid. It has the following structure:
Salicylic acid is a crystalline solid, and it is colorless. This substance was earlier isolated from the bark of the willow tree; thus it got the name from the Latin word salix, which is used to indicate willow tree. Molar mass of salicylic acid is 138.12 g mol-1. Its melting point is 432 K, and its boiling point is 484 K. Salicylic acid is soluble in water.
Aspirin has a similar structure as to salicylic acid. Aspirin can be synthesized from the esterification of the phenolic hydroxyl group of salicylic acid with the acetyl group from acetyl chloride. Salicylic acid is a plant hormone. It has a plant growth and development role in plants. Further it assists with photosynthesis, transpiration, ion uptake and transport in plants. In nature, it is synthesized within plants from the amino acid phenylalanine.
Salicylic acid is used for medicinal and cosmetic uses. Especially salicylic acid is used to treat acne prone skins to reduce pimples and acne. It is an ingredient in shampoos used to treat dandruff. Salicylic acid is also used as a medicine, to reduce fevers and ease aches and pains. It is also an essential micronutrient needed for human. Fruits and vegetables like dates, raisins, blueberries, guavas, tomatoes, and mushrooms contain salicylic acid. Not only salicylic acid, but its derivatives are also useful in different means.
What is the Difference Between Benzoyl Peroxide and Salicylic Acid?
The key difference between benzoyl peroxide and salicylic acid is that benzoyl peroxide belongs to the peroxide family whereas salicylic acid belongs to the carboxylic acid family. Moreover, benzyl peroxide has two benzene rings, while salicylic acid has only one benzene ring. Moreover, salicylic acid dissolves in water well compared to benzoyl peroxide. Compared to salicylic acid, benzoyl peroxide can be irritating for some skin types.
Summary – Benzoyl Peroxide vs Salicylic Acid
Benzoyl peroxide and salicylic acid are two chemicals that are largely used to treat acne. The key difference between benzoyl peroxide and salicylic acid is that benzoyl peroxide belongs to the peroxide family whereas salicylic acid belongs to the carboxylic acid family.