Schottky defect is observed in crystals when.....

Question:

Schottky defect is observed in crystals when.....

Answer: when equal numbers of cations and anions are missing from the lattice.

Explanation:

Schottky defect in crystals is observed when equal numbers of cations and anions are missing from the lattice. It is important that an equal number of cations and anions are missing, otherwise the electrical neutrality of the crystal will get affected.

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