Question

Why are ionic solids brittle while metallic solids are ductile and malleable?

Answer 1

Dear student!

The ionic crystals are hard because the positive and negative ions are strongly attracted to each other and we require a huge energy to break the strongest ionic bond and it is difficult to separate the ions, however, when pressure is applied to an ionic crystal then ions of like charge may be forced closer to each other. The electrostatic repulsion can be enough to split the crystal, which is why ionic solids are brittle also.