Home > Community > Which one of the following is the strongest Lewis acid, BF3, BCl3, BBR3, or BI3?
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+ Physical chemistry
+ Lewis acids
+ Lewis structure
+ Acids
+ Chemistry
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Omar N.

Which one of the following is the strongest Lewis acid, BF3, BCl3, BBR3, or BI3?

Ata Ur Rehman  Follow

People will think of BF3 as strongest lewis acid, but BI3 is stongest due to back bonding.

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Diana Smith  Follow

Larger the size of halide, lesser will be the effective overlap of orbitals of boron and halogen. Hence BI3 will be most acidic while BF3 be the least.

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Blessing Emmanuella  Follow

BI3>BBR3>BCl3>BF3, decreasing order of Lewis acid strength. This is due to decreasing order of extent of ppi-ppi back bonding.

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Angus Mccamant  Follow

The Lewis acid is really the boron atom because that’s the electronegative atom in the molecule. Polarized bonds in which boron’s substituents are more electronegative than boron leave the boron with a partial positive charge, increasing its electronegativity. All your compounds are halides of boron. Which halogen substituent is the most electronegative? Look up aluminum halides while you’re at it.

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Danilo Renzi  Follow

BI3 is the strongest lewis acid because the conjugate base of BI3 is most stable among all the other’s,so it's considered as strongest lewis acid.

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