The Lewis acid character of boron tri halides follows the order :

Question

The Lewis acid character of boron tri halides follows the order : (A) BCl 3> BF 3> BBr 3> BI 3 (B) BI 3> BBr 3> BCl 3> BF 3 (C) BBr 3> BI 3> BCl 3> BF 3 (D) BF 3> BCl 3> BBr 3> BI 3

Tardigrade Admin · Accepted Answer

Extent of back bonding, reduces down the group leading to more Lewis acidic strength

(2 p - 2 p) B F_{3} > (2 p - 3 p) BC l_{3} > (2 p - 4 p) BB r_{3} > (2 p - 5 p) B I_{3} (extent of back bonding)

B F_{3} < BC l_{3} < BB r_{3} < B I_{3} (lewis acidic nature)

Q. The Lewis acid character of boron tri halides follows the order :

$BC l_{3} > B F_{3} > BB r_{3} > B I_{3}$

$B I_{3} > BB r_{3} > BC l_{3} > B F_{3}$

$BB r_{3} > B I_{3} > BC l_{3} > B F_{3}$

$B F_{3} > BC l_{3} > BB r_{3} > B I_{3}$

Extent of back bonding, reduces down the group leading to more Lewis acidic strength
$(2 p - 2 p) B F_{3} > (2 p - 3 p) BC l_{3} > (2 p - 4 p) BB r_{3} > (2 p - 5 p) B I_{3} (extent of back bonding)$
$B F_{3} < BC l_{3} < BB r_{3} < B I_{3} (lewis acidic nature)$

Q. The Lewis acid character of boron tri halides follows the order :

BCl3​>BF3​>BBr3​>BI3​

BI3​>BBr3​>BCl3​>BF3​

BBr3​>BI3​>BCl3​>BF3​

BF3​>BCl3​>BBr3​>BI3​

Extent of back bonding, reduces down the group leading to more Lewis acidic strength (2p−2p)BF3​​>(2p−3p)BCl3​​>(2p−4p)BBr3​​>(2p−5p)BI3​​ (extent of back bonding) BF3​<BCl3​<BBr3​<BI3​ (lewis acidic nature)

$BC l_{3} > B F_{3} > BB r_{3} > B I_{3}$

$B I_{3} > BB r_{3} > BC l_{3} > B F_{3}$

$BB r_{3} > B I_{3} > BC l_{3} > B F_{3}$

$B F_{3} > BC l_{3} > BB r_{3} > B I_{3}$

Extent of back bonding, reduces down the group leading to more Lewis acidic strength
$(2 p - 2 p) B F_{3} > (2 p - 3 p) BC l_{3} > (2 p - 4 p) BB r_{3} > (2 p - 5 p) B I_{3} (extent of back bonding)$
$B F_{3} < BC l_{3} < BB r_{3} < B I_{3} (lewis acidic nature)$