Question

Which of the following does not posses any plane of symmetry?

• A. Cubic
• B. Monoclinic
• C. Triclinic
• D. Rhombohedral

Answer 1

The correct option is C Triclinic

Triclinic crystal lattice does not posses any plane of symmetry.

Plane of symmetry is that imaginary plane which passes through the centre of the crystal and divides it into two equal portions (just mirror images of each other).

For triclinic crystal system, $a\ne b\ne c,\alpha \ne \beta \ne \gamma ={90}^o$