Vish went to an electrical shop along with her father to purchase a bulb and some electrical equipment. After returning home, Vish looking at the bulb keenly and asked her father. "Is it filled with air or vacuum?" Her father told her that it was filled with nitrogen or argon. She asked him why the bulb could not be filled with air which is readily available, as nitrogen is obvious a part of air ? What was her father's correct explanation to her question ?

Explanation

Air cannot be filled in electric bulbs as air contains oxygen which oxidises the filament. Hence, inert gas like Ar or less reactive gases like nitrogen are used as it does not react with the metal filament.