Group Theory

What is the other name of Improper Axis of Symmetry?

• Rotation-Inversion

• Rotation-Reflection

• Reflection- Inversion

• None of the above

What is the Symmetry element in Centre of Inversion?

Pick the molecule which possess centre of symmetry.

• HCl

• o-dichlorobenzene

• H₂O

• p-dichloro benzene

Give the point group of HCl molecule .

• C $\infty$ v

• D $\infty$ h

• C2v

• D2h

List out all the symmetry elements possessed by NH₃ molecule.

• E, C3, $\sigma$ v1, $\sigma$ v2, $\sigma$ v3

• E,C2, $\sigma$ v1, $\sigma$ v2, $\sigma$ v3

• E, C2, $\sigma$ v1, $\sigma$ v2

• E, C3, $\sigma$ v1, $\sigma$ v2

Pick out a non planar molecule from the following list ?

• H₂O

• XeF4

• BF₃

• NH₃

Point groups are represented by .................symbols.

If a molecule possess the symmetry elements E, C2, $\sigma$ v1, and  $\sigma$ v2, then what will be the point group of the molecule .

• C3v

• C2h

• C2v

• D2h

Give the point group of BF₃ molecule.

If all the symmetry elements in a group commute with each other ,it is called ................