This substance chemically transforms when heat is applied.

This chemical synthesis reaction is very complex.

This problem is very complex and cannot be solved easily.

It is a very beautiful view.

I was amazed at his extraordinary talent.

Please press this button in case of emergency.

This chemical reacts when heat is added.

This chemical reaction is very dangerous.

Please use the emergency stairs in case of a fire.

Due to the earthquake, the city declared a state of emergency.