Yttrium2 - 5-5-2018 at 07:34
How is this done?
I took gen chem 1, but it's been along long time
Vosoryx - 5-5-2018 at 07:38
AFAIK the main two metals in tap water are Ca2+ and Mg2+
Carbonate precipitates both of these. That's the off white crust you often see around taps in areas without good water treatment. (I live on a well,
so it's very prevalent for me.)
I seem to remember it's done by bubbling CO2 through the water... or maybe just adding carbonic acid. I don't think that sodium carbonate is used
though, as that adds a sodium salt which could alter the taste of the water... not 100% on this though.
phlogiston - 5-5-2018 at 13:11
Not precipitation, but ion exchange could be used to extract/concentrate metal ions from tap water.