Question

$B{X}_{3}N{H}_3⟶B{X}_3.N{H}_3$ $\Delta H_f$ = Heat of formation of the adduct. The numerical value of $\Delta H_f$ is found to be maximum for:

• A. $B{F}_3$
• B. $BC{l}_3$
• C. $BB{r}_3$
• D. $B{I}_3$

Answer 1

The correct option is D $B{I}_3$

$B{I}_3$ is by far the strongest Lewis acid and thus the heat of adduct formation will be the highest in magnitude.