MCQ
The covalency and oxidation state respectively of boron in $\left[ BF _4\right]^{-}$, are
- ✓$4$ and $3$
- B$4$ and $4$
- C$3$ and $4$
- D$3$ and $5$
✓
Answer
Correct option: A.
$4$ and $3$
a
Number of covalent bond formed by Boron is $4$
Number of covalent bond formed by Boron is $4$
Oxidation number of fluorine is $-1$,
Oxidation number of $B +4 \times(-1)=-1$,
Thus, Oxidation number of $B =+3$
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