Question

Sodium rosinate is generally added to soap because it
A) Prevents rapid drying of soap
B) Produces a rich lather
C) Gives antiseptic property
D) Acts as a perfume

Answer 1

Hint: Rosinates is a type of detergent with a very complicated structural form. Sodium rosinate is extremely viscous and is diluted in an aqueous solution of sodium soap of tall oil rosin.

Complete Step by Step Solution:
Sodium rosinate is a type of rosin acid that is also commonly known as resin acid. They have a very complicated structural form and have the property which helps them in the mechanical protection of the air bubble that is formed in the soap. It acts as a stabiliser of foam by maintaining a proper air content in the medium.
Hence, option B is the correct answer

Additional Information Lathering in soaps is usually caused by an increase in the surface tension of water. An increased amount of surface tension is also one of the few mechanisms that help soap in cleaning.
Some other features of sodium rosinate are as follows:
1. It can be easily diluted with water and in the various aqueous solutions of water and glycols.
2. The emulsions that have been formed with sodium rosinate have proven to be highly stable.
3. When used in concrete, it delivers a longer setting time and the freeze-thaw resistance in concrete is highly improved.
Various applications of sodium rosinate are as follows.
1. It provides a variety of uses in the manufacturing of construction materials such as lubricants, paints, coatings, emulsions, chemicals, adhesives, etc.
2. It has very high air entertainment properties, it is also used by concrete, stucco, and mortar manufacturing industries for construction materials.
3. It also helps in designing soap solutions where the water content required is very low and of very low viscosity which makes it possible to pump the soap at very reasonable temperatures.

Note: Various other synthetic foam stabilisers are being used these days. Some of those stabilisers have polymeric anions while others may have very strong intermolecular attraction between them.