Sulphuric acid $(H_2SO_4)$ provides an example of:

The octet rule is not valid for which of the following molecules?

The number of $\sigma$ and $\pi$ bonds in $O_3$ molecule is:

Explain the formation of a chemical bond.

Identify the correct orders against the property mentioned:
$(A)$ $H_2O > NH_3 > CHCl_3$ - dipole moment
$(B)$ $XeF_4 > XeO_3 > XeF_2$ - number of lone pairs on central atom
$(C)$ $O-H > C-H > N-O$ - bond length
$(D)$ $N_2 > O_2 > H_2$ - bond enthalpy
Choose the correct answer from the options given below:

In which of the following pairs is the geometry around the central atom not the same?