MCQ
Oxidation number of cobalt in $K[Co{(CO)_4}]$ is
- A$+1$
- B$+3$
- ✓$-1$
- D$-3$
$1 + x + 0 = 0;\,\,x = - 1$.
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(Given $\ln 10=2.3, R =8.3 JK ^{-1} mol ^{-1}, \log 2=0.30$ )