MCQ
  Oxidation number of cobalt in $K[Co{(CO)_4}]$ is
  • A
    $+1$
  • B
    $+3$
  • $-1$
  • D
    $-3$

Answer

Correct option: C.
$-1$
c
(c)$K[\mathop C\limits^ * o{(CO)_4}]$

$1 + x + 0 = 0;\,\,x = - 1$.

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