" 19.Oil and fat containing food items are flushed with nitrogen.Why "

(a) Write one equation each for decomposition reaction when energy is supplied in the form of : (i) heat , (ii) light. (b) Account for the following : (i) Paint is applied on iron articles. (ii) Oil and fat containing food items are flushed with nitrogen . (iii) When an iron nail kept in copper sulphate solution, blue colour of the solution fades and iron nail becomes brownish .

Oils and fats are :

Which term is used to indicate the development of unpleasant smell and taste in fat and oil containing foods due to aerial oxidation (when they are kept exposed for a considerable time) ?