Chemical pollution has a serious impact on the health of the Earth.

This shirt is made of chemical fiber.

He is suffering from combat stress reaction.

It is reported that North Korea has conducted another underground nuclear test.

He is an expert in experimental psychology.

He is spending a lot of time on experimental research.

The concept of chemical equivalent is essential for understanding chemical reactions.

My company specializes in the manufacture of fine chemicals.

Chemotransmitters play an important role in the transmission of information between nerve cells.

Stoichiometry is a method for calculating the amount of substances in a chemical reaction.