$sp^3d^2$ hybrid orbitals are formed by the mixing of which atomic orbitals?

The hybridization states of the chlorine atom in $ClO_4^-$,$ClO_3^-$,and $ClO_2^-$ are respectively .....

Consider the following species: $BrF_5, XeF_5^-, BF_4^-, ICl_4^-, XeF_4, SF_4, NH_4^+, ClF_3, XeF_2, ICl_2^-$. Number of species having $sp^3d$ hybridized central atom is . . . . . . .

Which of the following statements is true regarding the $PCl_5$ molecule?
$(i)$ The two axial $P-Cl$ bonds in $PCl_5$ are longer than the three equatorial bonds.
$(ii)$ The axial bonds in $PCl_5$ are stronger than equatorial bonds.
$(iii)$ The axial bonds in $PCl_5$ are more stable than equatorial bonds.
$(iv)$ All five bonds in $PCl_5$ molecule are equivalent.

Why does boron trifluoride behave as a Lewis acid?

Match List-$I$ with List-$II$ :

List-$I$ (Species)	List-$II$ (Hybrid Orbitals)
$(a)$ $SF_{4}$	$(i)$ $sp^{3}d^{2}$
$(b)$ $IF_{5}$	$(ii)$ $d^{2}sp^{3}$
$(c)$ $NO_{2}^{+}$	$(iii)$ $sp^{3}d$
$(d)$ $NH_{4}^{+}$	$(iv)$ $sp^{3}$
	$(v)$ $sp$

Choose the correct answer from the options given below :