Answer: No reaction occurs.
Explanation:
A single replacement reaction is one in which a more reactive element displaces a less reactive element from its salt solution.
Copper lies lower in the reactivity series and thus is less reactive than lead. Only a more reactive element is able to displace a less reactive element from its salt solution. As copper is less reactive than lead , it cannot lose electrons and thus cannot displace lead.
\(Cu+Pb(NO_3)_2\rightarrow {\text {no reaction}}\)
