What is the reaction when a $Zn$ rod is kept in a copper nitrate solution?

(N/A) When a $Zn$ rod is placed in a copper nitrate solution,a displacement reaction occurs. $Zn$ is more reactive than $Cu$,so it displaces $Cu^{2+}$ ions from the solution.
The chemical reaction is:
$Zn_{(s)} + Cu^{2+}_{(aq)} \rightarrow Zn^{2+}_{(aq)} + Cu_{(s)}$
Observations:
$1$. The blue colour of the copper nitrate solution gradually fades and eventually disappears as $Cu^{2+}$ ions are reduced to metallic $Cu$.
$2$. $A$ reddish-brown deposit of metallic $Cu$ forms on the surface of the $Zn$ rod.
$3$. The solution becomes colourless due to the formation of $Zn^{2+}$ ions.