Ncert Exercises & Solutions

In which of the following compounds, the carbon marked with an asterisk is most electronegative?

1. ${CH}_{3} - {CH}_{2} - * {CH}_{2} - {CH}_{3}$

2. ${CH}_{3} - * CH = CH - {CH}_{3}$

3. ${CH}_{3} - {CH}_{2} - C \equiv * CH$

4. ${CH}_{3} - {CH}_{2} - CH = * {CH}_{2}$

Hint: Percentage of s character directly proportional to electronegativity

The electronegativity of carbon atoms depends on their state of hybridization. More s-character more is the electronegativity.

{sp}^{3} < {sp}^{2} < sp

25 % s 33 % s 50 % s

Thus, sp-carbon has the highest electronegativity, i.e., option (3) (

{CH}_{3} - {CH}_{2} - C \equiv * CH

) is correct.