Sciencemadness Discussion Board

Thermometer mishap in Sodium Acetate soln :(

Gearhead_Shem_Tov - 27-9-2010 at 23:57

OK, so my wife is out of town for two days, and I say to myself, "This is a great time to neutralise 20L of vinegar with sodium bicarb & boil it down to a supersaturated soln!"

Of course, that's too much to fit in one pot, but two stainless pots will do quite nicely, and the wife won't mind because it's only vinegar and bicarb and she won't find out. And there's even room for a bag of activated charcoal to clean up the crud discolouring the mixture.

Eight hours later, it's almost down to 2L total, the black brew (activated C, remember?) boiling away merrily at either 116 or 120, depending on which thermometer I believe, pH between 6.8 & 7.1, and I'm starting to plan how I'm going to filter all this mess to get rid of the carbon granules ...

Then my good thermometer slips and clunks on the pot bottom; I lift it gingerly to see ... the bulb is broken.

Shucks and other comments.

So. I have two litres of boiling solution contaminated with metallic mercury, now. Is there any way to save my sodium acetate? How about the stainless pan?

-Bobby

woelen - 28-9-2010 at 00:42

The sodium acetate won't be contaminated. Mercury does not dissolve in such a brew, not even at well over 100 C. So, you still can use that for experiments without worrying about being poisoned.

Whether the pan can still be used for cooking purposes depends on the type of pan. If it is really made of stainless steel, then the mercury does not adhere to it, mercury is absolutely non-sticking to iron. The same is true if the pan is covered inside with a teflon anti-caking coating. If the pan contains aluminium and this is exposed to the liquid, then I would not use it anymore for preparing food. Aluminium and its alloys can absorb mercury (and at such spots it corrodes like hell).

blogfast25 - 28-9-2010 at 06:02

Your pH doesn't seem to fit though, assuming neutralisation was complete, then sodium acetate is more alkaline than that. Or did you use an excess of vinegar to suppress hydrolysis?

As regards the pan, I believe even an aluminium pan could be saved by carefully scrubbing it with steel wool and concentrated washing soda. Like all alkalis it attacks aluminium (the extent depending strongly on conditions, of course), so that the layer that might contain some Hg should come off quite easily, unless it penetrated quite deeply of course.

woelen - 28-9-2010 at 09:40

Quote: Originally posted by blogfast25  
As regards the pan, I believe even an aluminium pan could be saved by carefully scrubbing it with steel wool and concentrated washing soda. Like all alkalis it attacks aluminium (the extent depending strongly on conditions, of course), so that the layer that might contain some Hg should come off quite easily, unless it penetrated quite deeply of course.
I would not rely on this for eating things. Of course it is fine to treat the pan like this and then use it for other non-food things (such as a water bath, a pan for boiling down things), but I would not eat anything from it anymore. You only have one body and one health.

Again, if the pan is made of iron, or if it has an intact teflon anti-caking coating, then I would have no problem using it for cooking. Just clean it well with hot water and soap and then rinse with water.

bahamuth - 28-9-2010 at 10:03

Once I was cleaning some mercury with conc. HCl in a stainless casserole, gently heating was applied(less than 100 degrees Celcius), then suddenly the mercury drop( about 0.05 mL) disappeared, leaving a little bump and a shinier spot in the stainless steel casserole, it had amalgamated to the casserole. Tried to scrape it with a stainless spatula, hard as steel it was.

Anyway, would easy eat a couple grams of mercury at once, but would not cook in metal ware contaminated with mercury, releasing the toxic metal slowly over the years, giving brain damage some ten-fifteen years later.

Rogeryermaw - 30-9-2010 at 11:36

i know mercury is dangerous but i accidentally broke a thermometer when i was a kid (couldn't have been more than 10 years old)and just let the mercury fall into my hand and let it roll around. i thought it was the coolest thing i ever saw and i didn't know any better. not even sure if i washed my hands before eating. still here though!

zed - 1-10-2010 at 11:39

Yes, but you have also adopted the name Roger-your-mom.

Hardly evidence of normal development.

True, most of the rest of us, have had lots of mercury exposure ourselves.

But, look at our pathetic state. We are just a bunch of scientist types.

Had we avoided all those toxic metals, our nervous systems might have developed to the point, that we could have become poets, or even rock musicians.

Rogeryermaw - 1-10-2010 at 14:27

Quote: Originally posted by zed  
Yes, but you have also adopted the name Roger-your-mom.

Hardly evidence of normal development.

True, most of the rest of us, have had lots of mercury exposure ourselves.

But, look at our pathetic state. We are just a bunch of scientist types.

Had we avoided all those toxic metals, our nervous systems might have developed to the point, that we could have become poets, or even rock musicians.


this is why i love this forum. you can not find intellectual wit like this in many other places. as for unusual development i blame my sister. she hooked me on monty python at a young age! i have actually played guitar for about 18 years and had a nice project jamming with a band for about 3 years until we had a big show in knoxville, ar. (i know, what in arkansas could possibly be big but for us 300 people was huge!)all that changed when we decided to get there at 10 am and didn't play till 9 pm. 11 hours for our drummer to drink and timing became a thing of the past. also if it was the toxic metals that molded my mind into what it has become, i wish i had drank a gallon of the stuff!

poets and rock musicians! we could even do better than that! we could be politicians banning chemicals! or better still we could be reality t.v. stars!

[Edited on 1-10-2010 by Rogeryermaw]

that's me on the right

[Edited on 1-10-2010 by Rogeryermaw]

me-show-juanitas.jpg - 42kB

Magpie - 2-10-2010 at 20:34

Nice pelt Roger! Better not get too close to an Indian reservation.:o

peach - 3-10-2010 at 14:43

I routinely don't wear gloves, goggles or masks when other people would. But I would write that pan off as far as cooking is concerned now.

Mercury on it's own is not particularly dangerous.

It is VERY dangerous once it starts forming salts, and some of those salts will sublime at low temperatures; causing them to 'disappear'. They haven't disappeared of coarse, they're now in the air and soon to be your blood stream (as they're highly water soluble in those forms, unlike mercury alone).

Our brains reach their maximum number of neurons around 20. But most of the learning we do and memories we have are created by interconnections between the neurons, that continue to form throughout the rest of our lives (going to bed and having dreams is almost certainly when our brains are cooking away at cementing the connections, the memories reappear and REM sleep deprived people have shit memories). For that to happen, dendrites (roots) need to extend out of the neurons and touch others as memories fire and cofiring factors draw the two cells to each other through a synaptic connection.

Mercury ions stall the growth cones that make that possible. From my memory, which may already be mercury poisoned, it takes only a single mercury ion to stall each growth cone. And they're not easy to get rid of.

As far as dissolving the stuff, I've done that with sulphuric. It had to sit in a conical with a 75mm bar beating the ass out of it in boiling 98% sulphuric for a good half hour to a few hours.

Still, given the tiny amounts required for it to start messing with your mind, best to assume enough of it has gone to a salt whenever there's an acid, long contact times and heat involved.

I'm guessing you're not planning to eat the sodium acetate. But don't use the pan, particularly if it's aluminium. Write on it in marker pen as well so your wife / kids don't pick it up and use it. Unless they've really been getting on your tits and you want the insurance money. :P

MORE DREAMY FACTS;

Our brains go through a repeating cycle throughout the night. There are waves, like Delta, that work like clock signals for the brain, it seems. Connecting an EEG to someone's head as they sleep shows the different waves up. They cycle down towards REM, the person starts to dream, and then they come back up. Then go back down, several times a night, and with each cycle getting less and less intense.

Gearhead_Shem_Tov - 4-10-2010 at 04:10

Quote: Originally posted by peach  
...
Mercury on it's own is not particularly dangerous.
... [but] ...
It is VERY dangerous once it starts forming salts, and some of those salts will sublime at low temperatures; causing them to 'disappear'. They haven't disappeared of coarse, they're now in the air and soon to be your blood stream (as they're highly water soluble in those forms, unlike mercury alone). ...


So, maybe it would make sense for me to try testing the sodium acetate and the pan -- definitely stainless steel, for the record -- for Hg and/or Hg salts? The only thing worse than having to remove a $90 pot from kitchen service would be Hg poisoning my nearest and dearest.

-Bobby

peach - 4-10-2010 at 08:45

Given the level of toxicity mercury compounds present, I would not trust a home test when it came to reusing the pan for cooking the dinner in.

They make the Emergency Planning Act's list of Extremely Toxic Substances.

The chloride is about 6 times more lethal than sodium cyanide, 13-14 times more so than arsenic, 16 times more so than strychnine (rat poison).

Cyanide will disappear provided it doesn't kill you whilst it's present (which doesn't last long). Mercury salts can not only be more immediately lethal, but will stay with you and cause you harm even if it doesn't reach the lethal stage.

I use tumblers from the kitchen all the time as stand in beakers. I wouldn't put one back if it'd had mercury in it. Mercury plus acid, I'd chip the rim and put it in the garage (out of sight & reach) or bin it.

Mercury salts are most certainly a lab glass only area.

[Edited on 4-10-2010 by peach]