Chapter Practice

 What are the main points of similarity and difference between valence bond theory and molecular orbital theory.

Arrange the given dicarbon species in order of their bond length giving reasons ${\mathrm{C}}_2, {{\mathrm{C}}_2}^{-}, {{\mathrm{C}}_2}^{2-}$.

Which two of ${{\mathrm{H}}_2}^{+}, {{\mathrm{H}}_2}^{-}$and ${{\mathrm{H}}_2}^{2-}$ have the same bond order?

In the following pair, predict which has higher value of the property mentioned and why?

$\mathrm{HF}, \mathrm{HCl}$: Polar character

In the following pair, predict which has higher value of the property mentioned and why?

${\mathrm{NH}}_3, {\mathrm{H}}_2\mathrm{O}$: Bond angle.

In each of the following pairs, predict which has higher value of the property mentioned and why?

 $\mathrm{KCl}, \mathrm{KF}$: Lattice enthalpy.

In the following pair, predict which has higher value of the property mentioned and why?

${\mathrm{NF}}_3, {\mathrm{NH}}_3$: Dipole moment.

 In the following pair, predict which has higher value of the property mentioned and why?

${\mathrm{C}}_2{\mathrm{H}}_2, {\mathrm{C}}_2{\mathrm{H}}_4$: $\mathrm{s}$-character in the hybridisation of carbon.