Easy MCQ +4 / -1 PYQ · JEE Mains 2021

In which one of the following molecules strongest back donation of an electron pair from halide to boron is expected?

  1. A BCl<sub>3</sub>
  2. B BF<sub>3</sub> Correct answer
  3. C BBr<sub>3</sub>
  4. D BI<sub>3</sub>

Solution

Type of back bonding<br><br>$$\matrix{ {B{F_3}} &amp; {BCl} &amp; {BB{r_3}} &amp; {B{I_3}} \cr {(2p\pi - 2p\pi )} &amp; {(2p\pi - 3p\pi )} &amp; {(2p\pi - 4p\pi )} &amp; {(2p\pi - 5p\pi )} \cr } $$<br><br>Therefore back bonding strength is as follows<br><br>BF<sub>3</sub> &gt; BCl &gt; BBr<sub>3</sub> &gt; BI<sub>3</sub>

About this question

Subject: Chemistry · Chapter: p-Block Elements · Topic: Group 13: Boron Family

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