Q. Find the total number of given phenomena in which hydrogen bonding plays a central role
(I) Ice floats in water
(II) Higher Lewis basicity of primary amines than tertiary amines in aqueous solutions
(III) Formic acid is more acidic than acetic acid
(IV) Dimerisation of acetic acid in benzene

 1354  176 Amines Report Error

Answer: 3

Solution:

In ice, water molecules are excessively -bonded giving a cage-like structure which is lighter than water. Primary amines are more basic than tertiary amine, because the protonated amines are extensively H-bonded and hence more stable than the corresponding protonated amines
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Acetic acid undergoes dimerisation in benzene
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