Hydrogen Bond

When hydrogen atom is present between two most electronegative atoms (N, O, F) then it is bonded to one by a covalent bond and to other by a weak force of attraction which is called hydrogen bond, etc. It is denoted by……

There are two type of hydrogen bonding :
(i) Intermolecular hydrogen bond
(ii) Intramolecular hydrogen bond

(i) Intermolecular hydrogen bond

Intermolecular hydrogen bond arises when hydrogen bonding occurs between two or more molecules. In this case m.p. & b.p. of compound increases due to molecular association.

....H —- F...         H —- F....         H -— F....

(ii) Intramolecular hydrogen bond

When hydrogen bonding occurs within a molecule then it is called intramolecular hydrogen bonding. Due to cyclisation m.p. & b.p. of the compound decreases in this case.

Due to intermolecular hydrogen bonding between alcohol and water, alcohol is soluble in water.

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