Question

Schottky defect in crystals is observed when ____________.

Options

• the foreign ions are found at the lattice sites in place of host ions

• unequal number of cations and anions are missing from the lattice

• an ion leaves its normal site and occupies an interstitial site

• equal number of cations and anions are missing from the lattice

Answer 1

Schottky defect in crystals is observed when equal number of cations and anions are missing from the lattice.

Explanation:

When one positive ion and one negative ion are missing from their respective positions, a pair of holes results.