Question

Which of these statements are correct?

• A. Deviations from ideal arrangement in entire rows of lattice points are called point defects
• B. Deviations from ideal arrangement around a point or an atom in crystalline substance are called line defects
• C. The irregularities in the crystal structure are called crystal defects
• D. $F$-centre gives lilac colour to $KCl$ crystal

Answer 1

Answer: (C), (D)

Irregularities or deviations from ideal arrangement in the entire rows of lattice points are called line defects, whereas deviations or irregularities from ideal arrangement around a point or an atom in crystalline substance are called point defects. All these irregularities are called crystal defects.
$F$-centre are responsible for the lilac colour of $KCl$.