Question

Detergents used for cleaning clothes and utensils contain?
A. Bicarbonates
B. Sulphonates
C. Nitrates
D. Bismuthates

Answer 1

Hint: Detergents are soluble in water and act as cleansing agents that combine with impurities and dirt to make them more soluble. The compound which is present in detergents is ester. They are non-oxidizing, colourless and stable in water.

Complete step by step solution:
As we all know, detergents are water soluble cleaning agents that combine with impurities and dirt to make them more soluble. They are sodium salt of long chain benzene sulphonic acid or the sodium salt of a long chain alkyl hydrogen sulphate. Furthermore detergents are classified into three categories.
Anionic detergents are mainly alkylbenzenesulfonates and in this type of detergent the alkyl benzene portion of these anions is lipophilic and the sulfonate part is hydrophilic.
Cationic detergents are very similar to anionic detergents. The cationic surfactants have ammonium ion as the polar end instead of the anionic sulfonate group.
Nonionic and zwitter ionic detergents are mainly based on polyoxyethylene or a glycoside.
So detergent used for cleaning purposes mainly contains sulphonates. Hence the correct option is (b).

Note: As we know that hard water contains calcium and magnesium ions so when detergent is added to hard water it does not forms scum because of the presence of \[ - SO_3^ - N{a^ + }\] at the end of molecules but soap forms scum with hard water. Hence detergent is preferred while using hard water.