Question

State the reasons for use of graphite
(i) as a lubricant for heated machine parts, 
(ii) as a lining for crucibles used in manufacture of high grade steel, 
(iii) as an electrode in electroplating.

Answer 1

1. Heavy machines which run very fast, when other lubricants are used catch fire, but graphite as lubricant when used parallel layers slide over one and other is non-volatile and non-sticky and reduces friction between rotating parts.
2. Graphite is used in refractory crucibles as graphite can withstand high temperature is a good conductor of heat.
3. Graphite as electrode in electroplating as graphite is good conductor of electricity relatively inert and almost does not react with acids.