Calling All Chem Geeks (incl. THE Chem Geek) re: storing pool chems

[chem geek]

As shown in this post, the freezing point of full-strength Muriatic Acid (31.45% Hydrochloric Acid) is -46.8 Celsius which is -52.2ºF so much colder than even the coldest winters in Maine.

Half-strength Muriatic Acid that is, say, 15-16% Hydrochloric Acid is 15.5 grams of HCl in 100 grams of solution so 100-15.5 = 84.5 grams of water. (15.5 g HCl / 36.46 g/mole HCl) / ((100-15.5) grams water / 1000 grams/kilogram) = 5.03 m. So, 5.03 m * (-1.86C/m) * 2 = -18.7 Celsius which is -1.7ºF so barely below freezing.

So this means that storing full-strength Muriatic Acid outdoor should be fine, but storing half-strength outdoors could freeze.

[waste]

Yet again, I find myself thanking you for your help!

If I can tap this resource 1 more time - Does potassium MPS (in 1 lb bags) outgas enough to damage the metals in the room it's stored in? I've got 17 bags and ~ nowhere to store them outside of the pump room (though, I do have a Styrofoam cooler I could put them in and leave outside).


You, and all the contributors here TRULY ROCK!!!!!!!!!!!


(Elsie, are you still with us here? I'm sorry to semi-hijack your thread )

[chem geek]

Though I am not certain, I doubt very much that non-chlorine shock (MPS) has any significant volatility. It's not like Trichlor pucks/tabs that can offgas chlorine (which you can tell by the smell when you open up a large container of pucks). Also, the container for the non-chlorine shock shouldn't be vented so if well sealed it shouldn't be a problem.

[CarlD]

But remember when it's below 0 F, the containers the MA is stored in get very, very brittle. Even hardened steel gets brittle and can shatter when it's that cold. I had a padlock on my gate I couldn't open when it was well below zero, and I whacked it with a pry bar and the hardened shank just snapped like an icicle! So imagine how fragile poly containers are!