Multiple choice

An electric bulb, on long use, forms a black coating on its inner surface due to

  1. melting of tungsten

  2. sublimation of tungsten

  3. oxidation of tungsten

  4. reduction of tungsten

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

An electric bulb, on long use, forms a black coating on its inner surface due to sublimation of tungsten.