Which of the following has a different number of $p_{\pi}-d_{\pi}$ bonds compared to the other molecules?

Which of the following cations is the most stable?

Which of the following species contains an equal number of $\sigma -$ and $\pi -$ bonds?

Choose the incorrect order of bond length $-$

Identify the correct statement among the following options.

$A$ tin chloride $Q$ undergoes the following reactions (not balanced):
$Q + Cl^{-} \rightarrow X$
$Q + Me_3N \rightarrow Y$
$Q + CuCl_2 \rightarrow Z + CuCl$
$X$ is a monoanion having pyramidal geometry. Both $Y$ and $Z$ are neutral compounds. Choose the correct option$(s)$.
$(1)$ The central atom in $X$ is $sp^3$ hybridized
$(2)$ The oxidation state of the central atom in $Z$ is $+4$
$(3)$ The central atom in $Z$ has no lone pair of electrons
$(4)$ There is a coordinate bond in $Y$