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प्रश्न
Why ionic crystals are hard and brittle?
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उत्तर
The ionic compounds are very hard and brittle. In ionic compounds, the ions are rigidly held in a lattice because the positive and negative ions are strongly attracted to each other and difficult to separate. But the brittleness of a compound is now easy to shift the position of atoms or ions in a lattice.
If we apply pressure on the ionic compounds the layers shifts slightly. The same charged ions in the lattice come closer. A repulsive force arises between the same charged ions, due to this repulsion the lattice structure breaks down chemical bonding.
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