Which one of the following conversions involves a change in both hybridisation and shape?

Sodium bicarbonate $(NaHCO_3)$ has:

What are the successes and failures of the Lewis theory in explaining chemical bonding?

The number of electrons in the valence shell of the central atom of a molecule is $8$. The molecule is

$A$ 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 $Y$

Match the following molecules in Column $I$ with the number of lone pairs on their central atom in Column $II$.

Column $I$ (Molecules)	Column $II$ (Number of lone pairs on central atom)
$A. \ NH_3$	$1. \ \text{Two}$
$B. \ H_2O$	$2. \ \text{Three}$
$C. \ XeF_2$	$3. \ \text{Zero}$
$D. \ CH_4$	$4. \ \text{Four}$
	$5. \ \text{One}$