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I was trying to isolate elemental bismuth from pepto bismol (bismuth subsalicylate) using the process seen here but after I added the HCl, instead of getting a pink foamy substance I got a white liquid with some white foam. The only reason I can think of, for why this would happen is that the pepto bismol was expired by a month. After I realized the reaction didn't work, I added a homemade universal indicator (red cabbage -Phenolphthalein- preserved with a little isopropyl alcohol) and started adding sodium hydroxide to neutralise any remaining acid. When I started adding the sodium hydroxide the solution started heating up and then changed color fairly rapidly from pink to a dull grey green which didn't change when I tried adding more acid. Shorty after the color change something started to precipitate out. I filtered off the precipitate and got a clear orange liquid. I then added a little HCl to the orange liquid and something immediately started precipitating out. The remaining liquid then turned clear and smells slightly like mint.

My only guess for what I have made is bismuth hydroxide (the first precipitate) but I have no idea what the second precipitate is. Here are pictures of the final precipitates.

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The initial filtration is purely awful lab technique. You cannot isolate a tiny bit of impure bismuth for less than it costs to buy a lot of very pure bismuth. metalshipper.com/bismuth.html <BR> amazon.com/Bismuth-Ingot-Chunk-99-99-Pure/dp/B001QUVMC8 <BR> rotometals.com/Bismuth-s/4.htm <BR> youtube.com/watch?v=s1CNGMElWfA youtube.com/watch?v=MMEkA2_N6vY <BR> Oh, yeah! –  Uncle Al Mar 17 at 20:33
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Can you give more details about your lab procedures? What concentration of HCl did you start with? What about the pepto? Did you use tablets or liquid? Etc. –  solarmist May 17 at 2:07

1 Answer 1

I'm not sure you did do the experiment wrong. I performed this experiment and it closely matched this video which had a light yellow liquid and foam.

Here are my results

After first filtration

I filtered it a couple more times to remove more foam. Then added the aluminum foil.

After aluminum foil

This is what I got at the end before I filtered the liquid out at the end.

In the end I was able to extract 6.2 grams of bismuth powder from 67 tablets of pepto (a bit less than the theoretical ~10 grams I was hoping to get).

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Also, the wiki page on Bismuth chloride show it is a yellow crystal in dry form. en.wikipedia.org/wiki/Bismuth_chloride –  solarmist May 19 at 20:04

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