I am the hardest existing form of coal with lowest levels of impurities. And I am relatively composed of pure carbon. What am i?
Who am I?
(a) I am found in clouds and mist.
(b) I am used in aerated drinks.
(c) I am used in an electric bulb.
(d) I form 78% of air.
(e) I am used in the production of nitric acid.