Liquid concentrate chemicals and freezing!

<p>I just remembered that the liquid concentrate B&W chemicals I recently purchase have been store in a unheated area of the house, uninsulated, and we have been having sub zero temps at night! Yikes. When I retreive them tonight is there even any sense in trying to revive them, or give them last rites and purchase all new!?</p>

<p>Have a look at them to see if there's been any crystallisation. If so, then the developer may well be beyond use. Let them warm up slowly to room temperature. You could always try developing a short length of exposed film, say half a dozen frames, to see if the developer is still active. Ditto, a short length of unexposed film to test the fixer.</p>

<p>I always used Kodak's rapid fix and it freezes at above 32 deg F and it always seemed to be fine--moved it out of the garage even though it was in Southern California!</p>

<p>A lot of the liquid concentrates (developers especially) contain high levels of sodium sulfite, other ionic materials, and some organic solvents, all of which will tend to depress the freezing point of the solution. They may not have crystallized at all.</p>

<p>If nothing has come out of solution due to the cold, no problem. Just get everything back up to processing temperature and you're good to go. If any solids have come out of solution from the cold, they might go back into solution when you warm the solutions back up to room temperature or a little warmer. If this is the case, then you're likely good to go. If you can't get any undissolved solids back into solution, then I'd chuck it and start over.</p>

<p>I had a very interesting surprise with my stop bath the first autumn after I got into photography. I learned that acetic acid froze around 15C.</p>

<p>I think there's some confusion here between freezing and precipitation of solute. </p>