Define transparent ,translucent ,opaque materials?

A transparent material is a material that

allows you to see right through it.

For example, glass is usually a transparent material.

A translucent material is a material that allows

you to see light, but it's distorted.

For example, tracing paper is a translucent material.

If a material is opaque, it blocks light from going through them.

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.