Octet rule and its limitations

Total number of lone pairs of electrons present in ${\mathrm{HClO}}_4$ is

What are the formal charges on $\mathrm{P}$ and $\mathrm{O}$ in the Lewis (electron dot) structure of the phosphate oxyanion represented in the figure?

Identify the name of the noble gas compound formed by the following reaction:

$\mathrm{Xe}\left(\mathrm{g}\right)+2\underset{\mathrm{excess}}{{\mathrm{F}}_2\left(\mathrm{g}\right)}\underset{7 \mathrm{bar}}{\overset{873 \mathrm{K} }{\to }}?$

Electron deficient species among the following is:

List some odd electron molecules.

Identify odd-electron molecules from the following:

Which of the following oxides is an odd-electron molecule.

Which among the following is least covalent in nature?

Why noble gases do not form compounds except krypton, xenon, and radon?

Which of the following noble gas compound has ${\mathrm{sp}}^3\mathrm{d}$ hybridisation?

What are the noble gases which form compounds?

If an element is represented by its Lewis symbols as   , then A may be

What will be the probable chemical formula if the valence shell of element $\mathrm{A}$ contain three electrons, while the valence shell of element $\mathrm{B}$ contain six electrons are combined?

In the Lewis structure, the formal charge on the central atom of ${\mathrm{SnCl}}_3^{-}$ is

Maximum number of lone pairs is present in Lewis dot structure of which compound?

How are sodium and chlorine atoms attain octet configuration in the formation of sodium chloride.

What are valence electrons? Write the number of valence electrons in the chlorine and carbon.

In ${{\mathrm{PO}}_4}^{3-}$ ion formal charge on the oxygen atom of $\mathrm{P}-\mathrm{O}$ bond is

The formal charge on the $\mathrm{O}$-atoms in the ion ${\mathbf{[}\mathbf{:}\ddot{\mathbf{O}}\mathbf{=}\mathbf{N}\mathbf{=}\ddot{\mathbf{O}}\mathbf{:}\mathbf{]}}^{\mathbf{+}}$ is