Give scientific reasons
It is recommended to use air tight container for storing oil for long time.

Explanation

When edible oil is left aside for long time, it undergoes air oxidation.
ii. Due to this, the taste and smell of oil changes and it becomes rancid. If food is cooked in this oil, its taste also changes.
iii. Thus, the oil will become unfit for consumption.
iv. The process of oxidation reaction of oil can be slowed down by storing it in air tight container. Hence, it is recommended to use air tight container for storing oil for long time.