Water - Potable Water

Potable water is defined as water which is filtered and treated to be safe for human consumption, free from harmful bacteria, germs, and suspended impurities.

The chemical formula of water is $H_2O$, representing two atoms of Hydrogen and one atom of Oxygen.

Characteristics of potable water: It should be transparent, colorless, odorless, and contain a small amount of dissolved gases like Oxygen ($O_2$) and minerals like salts of Calcium ($Ca^{2+}$) and Magnesium ($Mg^{2+}$).

Sedimentation and Decantation: A process where heavier insoluble impurities settle down. To speed up the settling of fine clay particles, Alum ($K_2SO_4 \cdot Al_2(SO_4)_3 \cdot 24H_2O$) is added in a process called 'Loading'.

Filtration: The process of removing suspended impurities by passing water through a filter (like sand or charcoal).

Boiling: A physical method of purification where heating water to $100^\circ C$ kills most of the disease-causing germs and bacteria.

Chlorination: A chemical method of purification where Chlorine ($Cl_2$) tablets or bleaching powder ($CaOCl_2$) are added to water to disinfect it.

Distilled water: The purest form of $H_2O$ obtained through evaporation and condensation. It is not ideal for drinking because it lacks essential minerals.