Question

How can we prove that natural water contains dissolved solids?

Answer 1

tap water comes from natural sources, lakes, rivers etc. before being purified it contains many more solutes and debris that come from all sorts of places. Once treated, majority of these impurities are removed, and trace amounts remain. also as water travels through piping, trace amounts of metal ions leech into the tap water hence the metallic taste. as for the gas, it is simply atmospheric air, which water slowly but invariably dissolves whenever the two come into contact..