When chlorine compounds are dissolved in pool water, the water becomes chlorinated.

Here's a breakdown:

* Chlorine compounds are chemicals like chlorine gas, sodium hypochlorite (bleach), or calcium hypochlorite.

* Dissolving means the chlorine compound breaks down into its individual components and mixes with the water molecules.

* Chlorinated water is water that contains dissolved chlorine. This chlorine acts as a disinfectant, killing bacteria and algae that can contaminate the pool.

So, while the water itself doesn't change its chemical composition (it's still H2O), the presence of dissolved chlorine compounds alters its properties and makes it suitable for swimming.