Explain the following terms with one example each:
(a) Corrosion (b) Rancidity

Explanation

(a) Corrosion : The process in which meals are eaten up gradually by the action of air, moisture or a chemical (such as an acid) on their surface is called corrosion. Rusting of iron is the most common example of corrosion. Rusting involves unwanted oxidation of iron metal which occurs in nature onits own. When an iron object is left in damp air for a considerable time, it gets covered with a red -brown flaky substance called rust. The corrosion (or rusting) of iron is a continuous process which, if not prevented in time, eats up the whole ironobject.
(b) Rancidity. Oxidation has damaging effect on foods containing gats and oils. When the food materials prepared in fats and oil are kept for a long time, they start giving unpleasant smell and taste. the condition roduced by the arerial oxidation of fats and oil in foods marked by unpleasant smell and taste is called rancidity. Rancidty spoils the food materials prepared in fats and oil which have been kept for a considerable time and makes them unfit for eating. For example is potato chips prepared inoil are kept exposed to air for a long time, they start giving unpleasant smell and taste due to the oxidation of oil present in them. The potato chips turn rancid and become unfit for eating.