Which of the following pairs are isoelectronic and isostructural: $NO_3^-$,$CO_3^{2-}$,$ClO_3^-$,$SO_3$?

Which one of the following is a correct set?

Which of the following statements is incorrect?
$(i)$ $NaCl$,being an ionic compound,is a good conductor of electricity in the solid state.
$(ii)$ In canonical structures,there is no difference in the arrangement of atoms.
$(iii)$ Hybrid orbitals form stronger bonds than pure orbitals.
$(iv)$ $VSEPR$ theory can explain the square planar geometry of $XeF_4$.

Fill in the blanks:
$(i)$ In $1927$,Heitler and London proposed the ........ theory.
$(ii)$ The ${\rm{ClF}}_3$ molecule has a .... shape.
$(iii)$ The number of bonding pairs in ions with a square planar shape is .......... .
$(iv)$ The value of the dipole moment in ${\rm{HBr}}$ is .......... .

In $XeO_3F_2$,the number of bond pair$(s)$,$\pi$-bond$(s)$ and lone pair$(s)$ on $Xe$ atom respectively are:

Identify the correct thermal stability orders among the following:
$(a) BeSO_4 < MgSO_4 < CaSO_4 < SrSO_4 < BaSO_4$
$(b) HF > H_2O > NH_3 > CH_4$
$(c) NH_3 > PH_3 > AsH_3 > SbH_3$
$(d) LiCl > BeCl_2 > BCl_3 > CCl_4$
$(e) Na_2CO_3 > MgCO_3 > Al_2(CO_3)_3$
$(f) Li_2CO_3 < Na_2CO_3 < K_2CO_3 < Rb_2CO_3 < Cs_2CO_3$