2007-03-29 12:50:47 · 5 answers · asked by Dom 2 in Science & Mathematics ➔ Chemistry
This is the amount of Ca++ and Mg++ in water. There are two kinds, permanent and temperorary. If you have carbonate, CO3=, that's permanent. If you have HCO3-, that's temporary, because heating the water carries out the conversion Ca(HCO3)2(aq) ==> CaCO3(s) + H2O + CO2(g).
2007-03-29 12:56:21 · answer #1 · answered by steve_geo1 7 · 0⤊ 0⤋
Presence of dissolved salts of calcium, magnesium etc. make the water hard. Even excess sodium like sea water makes the water hard. Soap doesn't give lather. Water leaves a scale after boiling.
2007-03-29 19:54:58 · answer #2 · answered by Swamy 7 · 0⤊ 0⤋
Measure of the calcium carbonate content in water. High hardness leads to white coatings on pots and "crud" in hot water heaters. It also causes soap not to stay "sudsy", since the soap serves as an ion-exchanger, and calcium-based soaps do not lather.
2007-03-29 19:56:08 · answer #3 · answered by cattbarf 7 · 0⤊ 0⤋
Like everyone else said, it depends on how much stuff is it in (like calcium)
I like softer water, it tastes better.
2007-03-29 20:00:23 · answer #4 · answered by Mako 7 · 0⤊ 0⤋
A measure of how much calcium is in the water.
http://en.wikipedia.org/wiki/Water_hardness
2007-03-29 19:53:07 · answer #5 · answered by John S 6 · 0⤊ 0⤋