MCQ
Correct order of Lewis Acidic strength?
- ✓$BF_3 < BCl_3 < BBr_3 < BI_3$
- B$BF_3 > BCl_3 > BBr_3 > BI_3$
- C$BF_3 = BCl_3 = BBr_3 = BI_3$
- D$BF_3 > BCl_3 < BBr_3 > BI_3$
✓
Answer
Correct option: A.
$BF_3 < BCl_3 < BBr_3 < BI_3$
a
(i) On the basis of back bonding, smaller be the halide atom, more effective be the back bonding and show less tendency to accept a pair of electrons.
(i) On the basis of back bonding, smaller be the halide atom, more effective be the back bonding and show less tendency to accept a pair of electrons.
(ii) Size of halides increase down the group, hence the ability of back bonding decreases making the molecule more acidic.
Hence, correct order of Lewis acid for boron-halides is $\mathrm{Bl}_{3}>\mathrm{BBr}_{3}>\mathrm{BCl}_{3}>\mathrm{BF}_{3}$
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
The $\Delta H_f$ for $CO_{2(g)},\,CO_{(g)}$ and $H_2O_{(g)}$ are $-393.5,\,-110.5$ and $-241.8\,KJ$ respectively. The standard enthalpy change for this reaction is
→$C{O_{2(g)}} + {H_{2(g)}} \to C{O_{(g)}} + {H_2}{O_{(g)}}$ .....$KJ$
$\ce{A_3L}$ container at $3$ atm pressure consist a mixture of $\ce{N_2}$ gas and $\ce{H_2O}$ vapours. Solid sphere of volume $0.5L$ is also present in same container. What will be the pressure of gas, if volume of container is reduced to $2L,$ at same temperature $(\ce{AQ}.$ tension $= 0.2$ atm$)?$
→Addition of $HCl$ to $3, 3$ -dimethyl- $1$ -butene yields two products, one of which has a rearranged carbon skeleton. Among the following carbocations, select the possible intermediates in that reaction ?
→$\mathop {{{(C{H_3})}_3}C\mathop C\limits^ + HC{H_2}Cl}\limits_1 $ $\mathop {{{(C{H_3})}_3}C\mathop C\limits^ + HC{H_3}}\limits_2 $ $\mathop {\begin{array}{*{20}{c}}
{{{(C{H_3})}_2}C\mathop C\limits^ + {{(C{H_3})}_2}} \\
{|\,\,\,\,} \\
{Cl\,\,\,}
\end{array}}\limits_3 $ $\mathop {{{(C{H_3})}_2}\mathop C\limits^ + CH{{(C{H_3})}_2}}\limits_4 $
The entropy changed involved in the conversion of $ 1 $ mole of liquid water at $ 373 \,K $ to vapour at the same temperature will be $[\Delta {H_{{\rm{vap}}}} = 2.257\,kJ/gm]$
→Assign $A, B, C, D$ from given type of reaction. $N{H_4}N{O_3} + \xrightarrow{\Delta }{N_2}O + {H_2}O$
→Which of the following statement is true. The entropy of the universe
Pure water is a $ ......... $ conductor of electricity :
→Order of base strength of the compounds
In endothermic reaction, the value of change in enthalpy $(\Delta H)$ is
→The bonds between $P$ atoms and $Cl$ atoms in $PC{l_5}$ are likely to be
→