Question

Match List-I with List-II:

List-I (System)	List-II (Axial lengths and angles)
(A) Cubic	(I) \(a = b = c, \alpha = \beta = \gamma = 90^\circ\)
(B) Tetragonal	(II) \(a = b \neq c, \alpha = \beta = \gamma = 90^\circ\)
(C) Orthorhombic	(III) \(a \neq b \neq c, \alpha = \beta = \gamma = 90^\circ\)
(D) Hexagonal	(IV) \(a = b \neq c, \alpha = \beta = 90^\circ, \gamma = 120^\circ\)

Choose the correct answer from the options given below:

• (A) - (IV), (B) - (II), (C) - (III), (D) - (I)
• (A) - (I), (B) - (III), (C) - (II), (D) - (IV)
• (A) - (IV), (B) - (II), (C) - (I), (D) - (III)
• (A) - (IV), (B) - (III), (C) - (II), (D) - (I)

Hint:

There are 7 crystal systems and these systems can be distinguished by analyzing the length of the axes and the angle between them. The axial relationship will determine the shape and symmetry of the crystal.

Answer 1

The Correct Option is B

Crystal systems are classified based on their axial lengths and angles:
• Cubic: All sides are equal, and all angles are 90°
• Tetragonal: Two sides are equal, one different, all angles 90°
• Orthorhombic: All sides unequal, all angles 90°
• Hexagonal: Two sides equal, one different, two angles 90° and one 120°
Therefore, the correct matching is: (A) - (I), (B) - (III), (C) - (II), (D) - (IV).