Alkali metals are very reactive chemically.

Metallic bonds are formed by ions floating in a sea of electrons.

His single word triggered a chain reaction, and everything changed.

She overreacted to his words.

Nuclear reactions are used for mass production of energy.

I was surprised by his overreaction.

His body showed a rejection reaction to the transplanted organ.

The use of chemical weapons is prohibited by international law.

Analytical chemistry is a science that reveals the composition and structure of substances.

I am majoring in physical chemistry at university.