Ans. (i) Hexagonal Unit cell Monoclinic unit cell
(1) Axial distances or edge
lengths a = b ≠ c a ≠ b ≠ c
(2) Axial angles α = β = 90° α = γ=90° β ≠ 90°
(3) Examples: Graphite, ZnO, CdS Monoclinic Sulphur, PbCrO2,
Na2SO4.10H2O
2 4 2
body-centred cubic