| A | B |
|---|
| water treatment | Purification processes applied to water before it is distributed for consumption |
| pre-chlorination | Addition of chlorine early in the water-treatment process to kill organisms |
| flocculation | Formation of an insoluble material suspended in or precipitated from a solution |
| post-chlorination | Addition of a low level of chlorine to treated water to prevent later bacterial infestation |
| aeration | Mixing of air into a liquid, as in water flowing over a dam |
| fluoridation | Addition of small quantities of fluoride ion to treated water supplies |
| chlorination | Adding chlorine to a water supply to kill harmful organisms |
| hard water | Water containing relatively high concentrations of calcium, magnesium or iron ions |
| ion exchange | Process of purifying water, which may involve the exchange of hard-water ions for other ions such as sodium |
| turbidity | Cloudiness |
| water softener | Apparatus containing an ion-exchange resin; used to treat water by removing ions that cause water hardness |
| regeneration | Renewing a material; renewing used ion-exchange resin by replacing hard-water ions in the resin with ions such as sodium |
