[Calcium123]

Hi guys,

I have a big problem with Calcium Chloride solution. My goal is to mix Calcium Chloride and water to get the solution with concentration of 186 g CaCl2 per 1 liter of water. And this sounds very simple. The problem is that every time I prepare the solution pH factor is around 10.

I'm not a Chemist but I'm working with a lot of Chemist who all say that I should get pH around 7 or slightly below but definitely not in alkaline region and they cannot explain this.

I've checked the water, btw I use redistilled water, also I tried using CaCl2 from different manufactures but every time it's the same. Btw I use proanalysi, pure (min 96%), anhydrous CaCl2 (powder).

I’ve searched over the net and everyone says that this is a neutral pH solution in theory but in practice things are obviously different.

If anyone has any practical experience with CaCl2 and water, please share with me.

Also, I’m not getting all the CaCl2 dissolved in water at 25 °C with approximately more than 8 hours of stirring. That is my second problem.

I would appreciate any suggestion.

Thank you 

[Hunter2]

The pH is alkaline according MSDS.

http://www.calciumchloride.co.uk/calcium_chloride_msds.html

http://www.sciencelab.com/msds.php?msdsId=9923251

But the solubility should be 750 g/kg in water at 25 ° C

So if you have still precipitate then your water contain to much Carbonate (carbondioxide) or the the salt is not pure.