Understanding chemical equations is difficult.

We are growing vegetables without using chemical fertilizers.

Understanding chemical equilibrium is very important in understanding chemical reactions.

This substance undergoes a chemical change when heat is applied.

In this experiment, you can observe a chemical reaction.

Gender identity refers to the gender that each individual recognizes themselves as.

In physics, blackbody radiation is a very important concept.

Cosmic background radiation is considered evidence of the Big Bang.

He attacked the enemy using a flamethrower.

He is facing many difficulties due to gender identity disorder.