Question

Arrange the B.E of (C - H) bonds indicated by $\alpha ,\beta ,\gamma$.

• A. $C-H_{ϵ}<C-H_{\alpha }<C-H_{\gamma }<C-H_{\beta }$
• B. $C-H_{\alpha }<C-H_{ϵ}<C-H_{\gamma }<C-H_{\beta }$
• C. $C-H_{\beta }>C-H_{\alpha }>C-H_{ϵ}<C-H_{\gamma }$
• D. None of these

Answer 1

The correct option is C $C-H_{\beta }>C-H_{\alpha }>C-H_{ϵ}<C-H_{\gamma }$

Refer to image

Stability of radical $\propto \frac{1}{bondStrength}\propto \frac{1}{BondEnegy}$

Stability: $C{H}_3-\stackrel{.}{C}{H}_2>C{H}_2=\stackrel{.}{C}>HC\equiv \stackrel{.}{C}$

Stability : $\underbrace{CH_2=CH-\overset{.}{C}H_2}_{alkyl\quad radical}> \underbrace{CH_3=CH_2-\overset{.}{C}H_2}_{alkyl\quad radical}$

Order of strength of $C-H$ bonds is:

$C-H_{\beta }>C-H_{\gamma }>C-H_{\alpha }>C-H_{ϵ}$