Explain: Ionic solids are hard and brittle.

Explain : Ionic crystals are hard and brittle.

Explain how vacancies are introduced in an ionic solid when a cation of higher valence is added as an impurity in it.

Explain how vacancies are introduced in an ionic solid when a cation of higher valence is added as an impurity in it.

Explain the structure of diamond and write why is it so hard?

Define lattice enthalpy of an ionic solid. Also give an example.

Explain the formation of scum when hard water is treated with soap.