Covalent Bond: A chemical bond formed by the sharing of two atoms.
Types of Covalent Bonds i. Single Covalent Bond: A type of bond formed by sharing of one pair of electrons between two atoms. ii. Double Covalent Bond: A type of bond formed by sharing of two pairs of electrons between two atoms. iii. Triple Covalent Bond: A type of bond formed by sharing of three pairs of electrons between two atoms.
Properties of Covalent Bond i. Their B.P. and M.P. is low because the intermolecular force is weak. ii. They are non conductors of electricity because they do not contain ions.
[Q*]. Carbon cannot form carbon cation [C4+] carbon anion [C4-]. Give reason.
[ANS]. They cannot form carbon cation because large amount of energy is required to remove four electrons by leaving six protons. Also, they can’t form carbon anion because six protons cannot hold ten electrons.
Versatile Nature of Carbon * Carbon exhibits a property called catenation.
The ability of carbon to form bond with another carbon is called catenation.
Catenation results in the formation of large number of molecules. * Carbon is tetravalent atom. Therefore one carbon atom can link with four different carbon or other monovalent atoms. * Carbon is small in size; therefore the chemical bond formed by carbon atom is strong.
Hydrocarbons: Compounds of hydrogen and carbon.
Hydrocarbons are grouped mainly into two, * Saturated: Carbon compounds in which only one pair of electrons are shared between two carbon atoms. * Unsaturated: Carbon compounds in which more than one pair of electrons are shared between two carbon atoms.
Based on the nature of the carbon chain they are grouped as, * Chain form * Branched form * Ring form
Alkane, Alkene and Alkyne……..
Alkane: Saturated hydrocarbons. Represented by a general form >> CnH2n+2
Alkenes: Unsaturated hydrocarbons. Double bond between two carbon atoms. Represented