Undissolving potassium chloride

Yo-han

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Feb 6, 2011
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Trying to make a KCl solution but the potassium chloride doesn't seem to dissolve. I use RO-water and tried 150 g/L (well below the max solubility) but the solution stays whitish. Not like milk but you can't see far through. Also there are still some crystals on the bottom. The KCl is brewsalt for water treatment. Might this be not pure enough? Or how do I check whether it is KCl at all?
 

Tom Barr

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Jan 23, 2005
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Sounds more like K2SO4, not KCL, KCL is clear/opaque or whitish sometimes and dissolves pretty fast(like NaCL).
If you use warm or hot water, the salts will all dissolve faster.
 

Yo-han

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Feb 6, 2011
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Tom Barr;94617 said:
Sounds more like K2SO4, not KCL, KCL is clear/opaque or whitish sometimes and dissolves pretty fast(like NaCL).
If you use warm or hot water, the salts will all dissolve faster.

I've both, they taste totally different:drunk: so I guess it's not K2SO4. I heated the bottle but no difference, besides the solubility at 0 degree celcius is way higher than 150g/L. Any other thoughts? Does burning it giving it a special color or something else I can easily do without an IR-spectrometer or something similar.
 

Yo-han

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Feb 6, 2011
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More than half was solved, so I tried tripling the amount of water, but still the dust remains. When leaving it for an hour, the solution turns clear. But after steering it up, it is cloudy again. I guess there is something in there which is not soluble. Will try the manufacturer or get me some other KCl.