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The problem of hard water

Lastly the slickness you feel on your skin when you have softened water does not come from the soft water but from the salt in the water which comes from the softening process. Its the same if you bath in sea water as any navy man will tell you. If you wash with distilled water you will not get that slippery feel.


In that case, salt softened water is even better for shaving IMHO. How does distilled water feel in comparison?
 
I majored in Physics, but they made me take a little Chemistry as well!

Hard water has calcium chloride in solution. Soap contains sodium stearate, and some potassium stearate, both of which will dissolve in water.

When mixed, the calcium wants to trade places with the sodium (and potassium). This leaves you with sodium chloride (ordinary table salt) and potassium chloride (sodium-free salt substitute) still dissolved in the water. And calcium stearate, which does not dissolve in water. This is the yellow-white scummy stuff that we see.

The problem is that the sodium and potassium stearates are what allows the soap to lather. The more calcium chloride in the water, the more sodium and potassium stearates get used up making calcium stearate, and until all the calcium chloride is converted to calcium stearate, no lather results. :frown:
 
I majored in Physics, but they made me take a little Chemistry as well!

Hard water has calcium chloride in solution. Soap contains sodium stearate, and some potassium stearate, both of which will dissolve in water.

When mixed, the calcium wants to trade places with the sodium (and potassium). This leaves you with sodium chloride (ordinary table salt) and potassium chloride (sodium-free salt substitute) still dissolved in the water. And calcium stearate, which does not dissolve in water. This is the yellow-white scummy stuff that we see.

The problem is that the sodium and potassium stearates are what allows the soap to lather. The more calcium chloride in the water, the more sodium and potassium stearates get used up making calcium stearate, and until all the calcium chloride is converted to calcium stearate, no lather results. :frown:

Huh? A water softener is an ion exchange process where the hard stuff is exchanged with either sodium chloride or potassium chloride so you wind up with a large amount of the NaCl or KCl which disolves away in the water which the hard stuff doesn't do. The soft water with the higher concentrations of these minerals makes all soaps lather like crazy. The purer the soap the more lather you get. Most soaps and detergents are not soaps at all but chemical concoctions designed to work in hard water. If you have a water softener you can get by, using a fraction of the amount of soaps you would normally use. The old water softener sales mans trick is take a vial of hard water and add a few drops of green liquid soap and shake, nothing happens. After you've added about 20 drops all you get is a blueish scum in the water. Do the same with soft water and with just 1 drop the vial looks like a glass of beer with a head of suds and the rest of the water xtl clear.
 
It does make you wonder why so many of us put up with hard water. I'd think eventually you'ld save so much money on soap, broken appliances, cleanings, new clothes etc. that it'd pay for itself. Surfactants make water wetter, that's my understanding (Van der Wahls forces holding the water together by soaps, if I remember correctly)- and hard water tends to counteract the effects of surfactants like soaps.
 
Huh? A water softener is an ion exchange process where the hard stuff is exchanged with either sodium chloride or potassium chloride so you wind up with a large amount of the NaCl or KCl which disolves away in the water which the hard stuff doesn't do. The soft water with the higher concentrations of these minerals makes all soaps lather like crazy.<snip>
:confused: My post was about what happens when you mix hard water and real soap. (Like in your salesman example.) It had nothing to say about water that's been run through a water softener, either ion-exchange or otherwise. Nothing to say about detergents or how salty water lathers better or anything else. Nothing to say about whether anyone should or should not install a water softener. Just the chemistry involved...that IS what happens, and what causes soap scum.:cool:
 
I majored in Physics, but they made me take a little Chemistry as well!

Hard water has calcium chloride in solution. Soap contains sodium stearate, and some potassium stearate, both of which will dissolve in water.

When mixed, the calcium wants to trade places with the sodium (and potassium). This leaves you with sodium chloride (ordinary table salt) and potassium chloride (sodium-free salt substitute) still dissolved in the water. And calcium stearate, which does not dissolve in water. This is the yellow-white scummy stuff that we see.

The problem is that the sodium and potassium stearates are what allows the soap to lather. The more calcium chloride in the water, the more sodium and potassium stearates get used up making calcium stearate, and until all the calcium chloride is converted to calcium stearate, no lather results. :frown:

Thanks for the mini-class! I've always wondered exactly what was happening with hard water.
 
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