Question

(a) What is anionic detergent? Write an example.
(b) Why are chemicals added to food? Write any two reasons.
(c) Write any one difference between broad spectrum and narrow spectrum antibiotics.

Answer 1

(a) Aanionic detergents have anions at the soluble ends of the chains. They are sodium salts of sulphonated long chains of hydrocarbons or alcohols. Examples include sodium n-dodecyl benzene sulphonate and sodium lauryl sulphate.
(b) Chemicals added to food to make food palatable, attractive and to increase its shelf life. Variety of chemicals are added to food like preservatives, colours, flavors, stabilizing agents, antioxidants, artificial sweeteners etc.
(c) Broad spectrum antibiotics are effective against a wide range of gram positive and gram negative bacteria whereas narrow spectrum antibiotics are effective against either gram positive or gram negative bacteria.