The correct order of the $O-O$ bond length in $O_2$,$H_2O_2$,and $O_3$ is:

Which of the following species is neither hypervalent nor hypovalent?

In the reaction $AlCl_3 + Cl^- \rightarrow [AlCl_4]^-$,$AlCl_3$ acts as a.......

Fill in the blanks given below:
$(i)$ The two theories based on the principles of quantum mechanics are ........ and ......... .
$(ii)$ The electronic configuration of carbon in the excited state is ........... .
$(iii)$ Through the combination of atomic orbitals,....... are formed.
$(iv)$ The ${\rm{CH}}_4$ molecule has a .......... shape.

The ratio of lone pair of electrons to bond pair of electrons in an ozone $(O_3)$ molecule is

What is the structure of $BeCl_2$ molecule in gaseous and solid state?