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

This shirt is made of chemical fiber.

The study of organic compounds is an important field in chemistry.

My child attends a supplementary school every Saturday.

He is suffering from combat stress reaction.

He understands the meaning of the proverb 'Teaching is half learning', which means that teaching leads to one's own learning.

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.