Question: What chemicals does water have?

Reka Nagy answered on 14 Nov 2016:

Pure water is made of oxygen and hydrogen – that’s why its chemical formula is H2O.
Most water you’ll find in nature, though, is not pure – so it contains traces of other elements like sodium, iron or potassium. Some spring waters can contain sulphur which makes them smell like rotten eggs! There’s a fair few of these in Romania, where I come from.

Tap water contains a small amount of chlorine as chlorine is used to disinfect the water.