I plan to work with an electrolyte that contains 1 g of Palladium(II) chloride. I am trying to estimate how much of a hazard this system could possibly pose (and provide ventilation, chlorine monitoring and other safety measures accordingly).

How would you go about determining what max. ppm concentration of chlorine might one need to expect in this case?

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    $\begingroup$ The question cannot be answered as is because determining ppm concentration would require knowledge of the approximate volume of your work space. With that information, it's basically a stoichiometry problem. $\endgroup$ – Zhe Aug 13 '19 at 2:25
  • $\begingroup$ What is of interest is the total maximum amount of chlorine released (a), the rate of it being released with an uncertainty range (b) and the volume which it is released into. One could create a simple formula from (a), (b), and (c) and learn about their relationships even if (b) and (c) are unknown or uncertain. In other words, just treat the volume as unknown variable x; or assume an enclosure of volume 50 liter if that is easier. $\endgroup$ – PhysicistDoingChemistry Aug 13 '19 at 22:14
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    $\begingroup$ Just assume all of the chlorine is released at once and you should have a upper bound. $\endgroup$ – Zhe Aug 13 '19 at 23:16
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    $\begingroup$ What's the point? It's not like magically whole thing would instantly turn into the gas and you'd breath in whole. In labs there are much more serious risks. $\endgroup$ – Mithoron Aug 13 '19 at 23:39
  • $\begingroup$ The point is exactly to estimate that risk. If you think there is no serious risk then that's great; please articulate to people less experienced in this area why that is and how to think about. $\endgroup$ – PhysicistDoingChemistry Aug 14 '19 at 16:07

Consider the molecular mass, and the mass of chlorine in 1 g of $\ce{PdCl2}$. Then consider the volume of the work space, and how quickly the $\ce{Cl2}$ disperses to fill that space.

Until it disperses, the concentration at the source might be 1E6 ppm (i.e. 100%), but is that meaningful? If it disperses to fill a flask, what is that volume? Are you doing this under a fume hood?

BTW, if no hood is available, you could enclose the reaction vessel(s) in a container with some sodium thiosulfate, $\ce{Na2S2O3}$, solution, which was used to absorb chlorine in gas mask canisters.

  • $\begingroup$ The sodium thiosulfate sounds like a great idea. It sounds like it would also help with any smell issues. Do you think it may be sufficient to just have an open dish with some sodium thiosulfate near the electrolysis cell inside the same enclosure (which is a 50 x 50 x 50 cm enclosure)? $\endgroup$ – PhysicistDoingChemistry Aug 14 '19 at 16:08
  • $\begingroup$ Is it a true enclosure (e.g. glove box)? In that case, a large pan (lots of surface area) or a piece of cloth soaked in the solution might suffice. If it's a fume hood, there should be no need for the thiosulfate. $\endgroup$ – DrMoishe Pippik Aug 14 '19 at 17:50
  • $\begingroup$ The enclosure is basically a temperature-controlled fridge. It's not 100% airtight but close. I could add some basic air exchange but it would complicate things. I'll probably go with the large pan of sodium thiosulfate and accept that small amounts of Cl2 will gradually leak out into the ambient (which is reasonably well ventilated). $\endgroup$ – PhysicistDoingChemistry Aug 15 '19 at 2:11

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