True or False. Opacity is a measure of how much light is blocked when it passes through a substance.

True

Explanation:

The word "Opacity" is tied to the property of the materials in blocking much of the light.

Opacity depends on the degree of light passing through a material. When the light is largely blocked, it is said that the material is opaque. If the flow of light passing is quite large, the material is considered translucent. And if the light goes through the material in its entirety, this is a transparent material.