Explain why ${\mathrm{CO}}_3^{2-}$ ion cannot be represented by a single Lewis structure. How can it be best represented?

Predict the hybridisation of each carbon in the molecule of organic compound given below. Also indicate the total number of sigma and pi bonds in this molecule.

Group the following as linear and non-linear molecules :

${\mathrm{H}}_2\mathrm{O}, \mathrm{HOCl}, {\mathrm{BeCl}}_2, {\mathrm{Cl}}_2\mathrm{O}$

Elements $\mathrm{X}, \mathrm{Y}$ and $\mathrm{Z}$ have $4, 5$ and $7$ valence electrons respectively.

(i) Write the molecular formula of the compounds formed by these elements individually with hydrogen.

Elements $\mathrm{X}, \mathrm{Y}$ and $\mathrm{Z}$ have $4, 5$ and $7$ valence electrons respectively.

Which of these compounds will have the highest dipole moment?

Draw the resonating structure of

Ozone molecule

Predict the shapes of the following molecules on the basis of hybridisation.

$\mathrm{BC}{l}_3, {\mathrm{CH}}_4, {\mathrm{CO}}_2, {\mathrm{NH}}_3$