MCQ
How many bonds (bond order) does $B_2$ have ?
- A$0$
- ✓$1$
- C$2$
- D$3$
✓
Answer
Correct option: B.
$1$
b
The $B _2$ molecule is known to be formed by the combination of two Boron atoms, where they are linked by a covalent bond.
The $B _2$ molecule is known to be formed by the combination of two Boron atoms, where they are linked by a covalent bond.
The atomic number of boron is $5$ , for which the electronic configuration of boron can be given as: $1 s^2\, 2 s^2\, 2 p^1$
The molecular orbital diagram for $B _2$ molecule can be shown as:
From the diagram, we can know that the number of electrons in bonding molecular orbitals is $4$ whereas the number of electrons in antibonding molecular orbitals is $2.$
Hence, the bond order is calculated as:
Bond order $=\frac{1}{2}(4-2)$
$=1$
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