pH Buffer Solution going crazy (a chemistry question)

[RalphLambrecht]

To protect the electrode of my pH meter, I keep it in a self-made, 3-mol potassium-chloride buffer solution. It has been it for about a year, and the only thing I've ever noticed in the past was a large (1-inch square) crystal forming in the buffer solution.

I recently went on a vacation for 3 weeks, turning off the heating while I was gone. The house got as cold as 12C but not less than that. When I came back, I noticed that the pH meter and the container it sits in (holding the buffer solution), looked like frozen over, KCl everywhere. The pH meter and the container were covered.

What happened, and how can this be prevented?

 

[Photo Engineer]

Saturated KCl at room temp will crystallize if cooled off. You caused this to happen by lowering the room temp.

Bring everything up to 20C and it should go back in, or soak in Satd. KCl at 80C and everything should be ok.

PE

 

[RalphLambrecht]

Saturated KCl at room temp will crystallize if cooled off. You caused this to happen by lowering the room temp.

Bring everything up to 20C and it should go back in, or soak in Satd. KCl at 80C and everything should be ok.

PE

Thanks PE, I will do that, but what made it leave the container and crawl all over the pH meter?

 

[heespharm]

Kcl evaporate then crystalizing??

 

[Photo Engineer]

Thanks PE, I will do that, but what made it leave the container and crawl all over the pH meter?

Surface tension will lead to creep. This is what forms the meniscus in any liquid contained in a thin tube. It will creep up the edges and over and down the outside.

PE