Question

What are the two properties of carbon which lead to the huge number of carbon compounds we see around us?
A.(i) Catenation (ii) Tetravalency
B.(i) Catenation (ii) Trivalency
C.(i) Catenation (ii) Pentavalency
D.(i) Covalency (ii) Divalency

Answer 1

We know that carbon is the chemical element with the symbol C and atomic number 6. It belongs to group 14 on the periodic table, it is nonmetallic and tetravalent. The most common isotope of carbon contains 6 protons and 6 neutrons, and has an atomic mass of 12.0107 amu.

Complete step by step answer:
We know that carbon shows various allotropic forms. Diamond has the hardest structure whereas graphite is one of the softest substances.
Diamond is transparent, and can be used as an electrical insulator and thermal conductor, whereas graphite is opaque, thermal insulator and good conductor of electricity. Other allotropes of carbon include carbon nanofoam, nanotubes, amorphous carbon, buckyballs, and glassy carbon.
Carbon shows affinity for linking with small atoms by the formation of covalent bonds. Carbon does not react with chlorine, any alkali metal, hydrochloric acid, sulfuric acid. Carbon oxides are formed when carbon reacts with oxygen at higher temperatures, and metal carbides are formed when carbon reacts with metals.
Very long chains of stable and interconnecting C-C bonds are formed by carbon. This property permits for the formation of various numbers of compounds.
The two important properties, which give leads to formation of large number of carbon compounds, are:
1.Catenation
2.Tetravalency
We can define catenation as the capability to form several bonds with other atoms of carbon leading to large molecules.
Tetravalency is the capacity of carbon to form bonds with four other atoms due to its valence 4. Compounds of carbon are produced with oxygen, nitrogen, hydrogen, sulphur, chlorine and many other elements, leading to compounds with definite properties that depend on the elements other than the carbon present in the molecule.

$\therefore$Option (A) is correct.

Note:
We have to know that carbon is formed inside stars when they burn helium in reactions of nuclear fusion. It is the fourth most abundant element in the universe. Pure form of carbon has low toxicity. Carbon in the form of coal, can be used as a source of fuel. We can use carbon black as black pigment in printing ink. We can use graphite in pencil tips, electrodes, and dry cells. We can use diamonds for cutting, grinding, polishing and drilling in industry.