What are common uses for carbon?
Carbon is commonly used in the form of hydrocarbons, such as fossil fuel, methane gas, and crude oil (petroleum). When crude oil is distilled in refineries, it makes gasoline and kerosene. Charcoal is basically impure carbon, which is created when burning an organic substance with the absence of air. It is a popular drawing material used in art, for grilling, and sometimes when smelting iron.
Diamonds are often used for polishing, grinding, drilling, or cutting glass, metals, and other materials.
Graphite mixed with clay works well as pencil lead since it rubs off so easily. It can also be used as a lubricant. This allotrope of carbon is used as a refractory, as well. Graphite is used to line ovens to protect them high temperatures because of its resistance to heat.
Hope this helps :D