Symmetry And Group Theory

Question 1

Symmetry operation that causes no change in a molecule.

Answer 1

Identity

Question 2

Symmetry operation possessed by all molecules

Answer 2

Identity

Question 3

Symmetry operation wherein a rotation by 360/n leaves the molecule unchanged

Answer 3

N-fold rotation

Question 4

By convention, rotations are ___ about the axis

Answer 4

Counterclockwise

Question 5

Symmetry operation that uses a mirror plane

Answer 5

Reflection

Question 6

Types of mirror planes
Varallel
Herpendicular

Answer 6

Dihedral: specialized varallel that bisects the angle between two C2 axes

Question 7

Symmetry operation that consists of n-fold rotation (herpendicular) followed by reflection

Answer 7

Improper rotation

Question 8

The value of n for improper rotation must always be >2 because S1=mirror plane and S2=inversion

Question 9

Set of symmetry operations that descirbes the molecules overall symmetry

Answer 9

Point groups

Question 10

Recall point groups and practice

Answer 10

Practice symmetry questions