The air in this area is greatly affected by pollutants emitted from factories.

We exist as a part of the material world.

Are you really not going to use this unused laptop?

He is the most competent employee of our company.

Who is the user of this software?

This bottle is reusable.

He is dedicated to the study of immunochemistry.

Thermochemistry is a part of chemistry that deals with the reactions of heat and matter.

This chemical reaction is very dangerous.

This shirt is made of chemical fiber.