Class 11 Chemistry - Chapter Hydrocarbons NCERT Solutions | Arrange benzene, n-hexane and ethyne in
Arrange benzene, n-hexane and ethyne in decreasing order of acidic behaviour. Also give reason for this behaviour.
Acidic character of species is defined on the basis of ease with which it can lose its H-atoms.
The hybridization state of carbon in the given compound is:
As the s-character increases, the electronegativity of carbon atom increases and the electrons of C-H bond pair lie closer to the carbon atom. As a result, partial positive charge of H- atom increases and H+ ions are set free.
The s-character increases in the order:
sp3 < sp2 < sp
Thus, the decreasing order of acidic behaviour is Ethyne > Benzene > Hexane.
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