- Home
- Standard 11
- Chemistry
p-Block Elements - I
medium
$B{X_3} + N{H_3}\ \xrightarrow {R.T}\ B{X_3}.N{H_3} +$ Heat of adduct formation $\left( {\Delta H} \right)$ The numerical value of $\Delta H$ is found to be maximum for
A
$BF_3$
B
$BCl_3$
C
$BBr_3$
D
$BI_3$
Solution
$\mathrm{BX}_{3} \cdot \mathrm{NH}_{3}$
Adduct form $^{\mathrm{n}}$ order $\mathrm{BI}_{3}>\mathrm{BBr}_{3}>\mathrm{BCl}_{3}>\mathrm{BF}_{3}$
As in $\mathrm{BF}_{3}$ strong back bonding occur. So adduct form $^{\mathrm{n}}$ decreases. Back bonding $\alpha \frac{1}{\text { adduct }}$ form $^{\text {n }}$
Standard 11
Chemistry
