Question

In which of the following molecules, a plane of symmetry is present?
A)

B)

C)

D) both A and C

Answer 1

Hint: We have to know that molecular symmetry is one of the main concepts of chemistry. Symmetry means nothing but similarity present in the molecular structure. This symmetry concept is used for the classification of molecules. The symmetry of the molecules is used for the study of the chemical properties. This kind of symmetry studies is mainly used for the dipole-dipole moment and group theory studies in chemistry.

Complete answer:
The given structures are
A)

B)

C)

Plane of symmetry is nothing but one imaginary plane we consider that should give similar structure in original molecules. In some many imaginary planes will come in intersecting axes. Like (xy, yz and xz)
According to the above discussion, we conclude plane of symmetry is present in

and

Hence, option D is correct, because the plane of symmetry is present in structure A and C.

Note:
There are three types of symmetry in chemistry molecules. There are planes of symmetry, axis of symmetry and center of symmetry. This classification of symmetry is based on how symmetry molecules will arise in operation. Axis of symmetry is nothing but one imagination axis come in rotation of molecules in specific axis, we consider that should give similar structure in original molecules. In some many imagination axes will come in intersecting axes. Like (x, y and z). Center of symmetry is nothing but one imaginary point coming in molecules in direction, we consider that should give similar structure and group in original molecules. In some many imaginations, points will come in the center of a molecule. The center of symmetry is also called the point of symmetry. Identity, rotation-reflection axis, plane of symmetry, axis of symmetry and center of symmetry are five key operations for the group classification of elements in group theory.