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2 votes
0 answers
38 views

Salts solubility and speciation calculations using PHREEQC

I am collecting data from literature for CO2 solubility in aqueous solutions. These are usually synthetic brines and are reported as molalities or wt% of salts or salt mixtures (I have NaCl, KCl, ...
Abdeldjalil Latrach's user avatar
-5 votes
1 answer
59 views

Why is 10 times phosphate-buffered saline more acidic (~6.9) than 1 time phosphate-buffered saline (~7.4)? [closed]

Recently, I've been told that similar pH shift (of about 0.5 units) was observed with 20 times NPS solution as well. In case of NPS the authors provide the following recipe for the 20 times solution: ...
abc's user avatar
  • 111
-2 votes
2 answers
732 views

Isolating potassium chloride from sodium chloride and potassium hydroxide

Assume that you have an aqueous solution of sodium chloride and potassium hydroxide. Is it possible to isolate potassium chloride from this? $$\ce{Na+(aq) + Cl-(aq) + K+(aq) + OH-(aq) -> Na+(aq) + ...
user avatar
0 votes
1 answer
787 views

Why is the enthalpy of solution of hydrated calcium chloride positive?

My book says that the enthalpy of solution of anhydrous calcium chloride is negative because it produces hydrated calcium chloride. But when hydrated calcium chloride is dissolved in water, the ...
Tahsin Choudhury's user avatar
41 votes
3 answers
11k views

Which "exotic salt" can lower water's freezing point by 70 °C?

The Medium.com article Mars Phoenix Lander, 10 Years Later shows several remarkable images and discoveries on Mars by the Mars Phoenix Lander circa 2008. One image (shown below) shows what looks like ...
uhoh's user avatar
  • 5,900