Which of the following does not exist in free form?

Question

Which of the following does not exist in free form? (A)  BH3  (B)  BF3  (C)  BCl3  (D)  BBr3

Tardigrade Admin · Accepted Answer

BH3 does not exist in free form because H-atoms in BH3 have no free electrons to form pπ -ρ π back bonding and thus boron has incomplete octet and hence BH3 molecule dimerise to form B2H6.

Q. Which of the following does not exist in free form?

$B H_{3}$

$B F_{3}$

$BC l_{3}$

$BB r_{3}$

$B H_{3}$ does not exist in free form because H-atoms in $B H_{3}$ have no free electrons to form $p π - ρ π$ back bonding and thus boron has incomplete octet and hence $B H_{3}$ molecule dimerise to form $B_{2} H_{6} .$

Q. Which of the following does not exist in free form?

BH3​

BF3​

BCl3​

BBr3​

BH3​ does not exist in free form because H-atoms in BH3​ have no free electrons to form pπ−ρπ back bonding and thus boron has incomplete octet and hence BH3​ molecule dimerise to form B2​H6​.

$B H_{3}$

$B F_{3}$

$BC l_{3}$

$BB r_{3}$

$B H_{3}$ does not exist in free form because H-atoms in $B H_{3}$ have no free electrons to form $p π - ρ π$ back bonding and thus boron has incomplete octet and hence $B H_{3}$ molecule dimerise to form $B_{2} H_{6} .$