This chemical reaction is very dangerous.

I observed precipitation in a chemistry experiment.

In this chemical reaction, the substance precipitates.

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

What is this material made of?

He is majoring in chemistry at university.

This chemical reacts when heat is added.

This chemical reaction is very dangerous.

He is an expert in chemistry.

The existence of dark matter has not yet been fully proven.