Question

Which of the following is true for orthorhombic primitive unit cell?

• A. All axial angles are equal to ${90}^{\circ }$
• B. None of the axial angles are equal to each other.
• C. All edge lengths are equal.
• D. Two axial angles are equal to ${120}^{\circ }$

Answer 1

The correct option is A All axial angles are equal to ${90}^{\circ }$

In Orthorhombic, all the axial angles are equal to ${90}^{\circ }$ while all the edge lengths are unequal.
$\alpha =\beta =\gamma ={90}^{\circ }$, $a\ne b\ne c$
Examples include Rhombic sulphur,$KN{O}_3,BaS{O}_4$