Chemistry - Carbon


  • Carbon is a non-metallic and tetravalent element.

  • Tetravalent means – carbon makes four electrons available to form the covalent chemical bonds.

  • Carbon has three isotopes that occur naturally – namely 12C, 13C, and 14C.

  • Among them, 12C and 13C are stable, but 14C is a radioactive isotope. Half-life of 14C is about 5,730 years.

Salient Features of Carbon

  • The physical properties of carbon largely depend on its allotropes.

  • Major allotropes of carbon are graphite, diamond, and amorphous carbon.

  • Graphite is opaque, black, and very soft; hence, it used to form a streak on the paper.

  • Diamond very hard (the hardest naturally occurring material) and transparent.

  • Graphite is a good conductor of electricity.

  • Diamond is bad conductor of electricity.

  • Carbon most likely has the highest sublimation point among all the elements.

Occurrence of Carbon

  • In terms of mass, carbon is the fourth most abundant chemical element found in the universe (after hydrogen, helium, and oxygen).

  • Carbon is available in abundance in the Sun, stars, comets, and in the atmospheres of most of the planets.

  • Carbon is found in the earth’s atmosphere and dissolved in water.

  • Hydrocarbons, such as coal, petroleum, and natural gas, all of them contain carbon.

  • Carbon is also found in methane hydrates, which found in polar regions and under the seas.

  • Some of the rocks enriched of carbon are coal, limestone, dolomite, etc.

  • Coal is very rich in carbon; hence, it is the largest commercial source of mineral carbon.

  • Coal shares about 4,000 gigatonnes or 80% of total fossil fuel.

Compounds of Carbon

  • Following are the major compounds of Carbon −

    • Cyanogen - CN2

    • Hydrogen cyanide - HCN

    • Cyanamide - CN2H2

    • Isocyanic acid - HNCO

    • Cyanogen chloride - CNCl

    • Chlorosulfonyl isocyanate - CNClO3S

    • Cyanuric chloride - NCCl3

    • Carbon disulfide - CS2

    • Carbonyl sulfide - OCS

    • Carbon monosulfide - CS

Uses of Carbon

  • Depending upon the allotrops, carbon is used in range of applications.

  • Carbon is one of the most essential elements of life without it, we cannot imagine life on the earth.

  • The fossil fuel namely methane gas and crude oil (petroleum), coal etc. are used in everyday life.

  • Graphite, combining with clay, used in making 'lead' used in pencils.

  • Charcoal is also used as a drawing material in artwork, iron smelting, barbecue grilling, etc.

  • Diamond is usually used in jewelry.

  • Industrial diamonds are used in cutting, drilling, and polishing tools for machining the metals and stone.

  • Fossil hydrocarbons, and carbon fiber are used in making plastic.