- A$Cu$
- B$Zr$
- C$Al$
- ✓$Ni$
The reactions are:
$Ni +4 CO \rightarrow Ni ( CO )_4$
$Ni ( CO )_4 \rightarrow Ni +4 CO$
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$\begin{array}{*{20}{c}}
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,OH} \\
{\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,|} \\
{C{H_3}{\text{ }} - {\text{ }}CH{\text{ }} = {\text{ }}CH{\text{ }} - {\text{ }}C{H_3}\xrightarrow{{{H_3}{O^ + }}}\,C{H_3} - C{H_2} - CH - C{H_3}}
\end{array}$
The compound $B$ is