Sciencemadness Discussion Board

thallium chemistry

woelen - 5-1-2017 at 11:41

I decided to start the year with some new and uncommon chemistry. I have some thallum(I) nitrate and thallium(III) oxide. Both allow interesting experiments to be performed:

Go to the following page and in the pattern search field type 'thallium' and press enter.

http://woelen.homescience.net/science/chem/exps/index2a.html

Thallium is especially interesting in combination with iodates and periodates. You may find this an interesting read and if someone of you has access to thallium compounds, then you may give it a try as well.

Beware: thallium and its compounds are very toxic. Toxicity is comparable to that of mercury, so be careful and be sure that you do not get exposed to thallium salts (e.g. by inhaling fine dust or fine droplets of an aerosol from a bubbling solution).

fluorescence - 5-1-2017 at 14:01

That's really nice ;)


I started doing some Thallium experiments in summer this year but only managed to bring three of them to youtube. I guess you have checked a lot of preparative literature as well but there doesn't seem to be that much on this quite interesting element unfortunately.

I didn't know you could dissolve the Tl(III) in Nitric acid, that might be something I could try as well....

woelen - 5-1-2017 at 14:23

The dissolving in hydrochloric acid is easiest, due to complex formation of TlCl4(-). In nitric acid and perchloric acid you get free Tl(3+) ions, but these are VERY prone to hydrolysis to hydrous Tl2O3 and that makes dissolving Tl2O3 in one of these acids so hard. But for sure, dissolving in 20% HNO3 or so works, albeit slowly.

I intend to repeat all of my experiments and make pictures of that so that I can make a nice colorful webpage of it. Thallium is quite interesting. It also seems to be possible to create deep red precipitates of this, I have to investigate how this can be done.

diddi - 5-1-2017 at 15:39

I will be watching with interest. I have some Thallium at my disposal and I love pretty colours!

chornedsnorkack - 6-1-2017 at 11:47

Quote: Originally posted by woelen  
The dissolving in hydrochloric acid is easiest, due to complex formation of TlCl4(-). In nitric acid and perchloric acid you get free Tl(3+) ions, but these are VERY prone to hydrolysis to hydrous Tl2O3 and that makes dissolving Tl2O3 in one of these acids so hard. But for sure, dissolving in 20% HNO3 or so works, albeit slowly.

Does thallium(III) also dissolve in sulphuric acid?

fluorescence - 6-1-2017 at 13:22

It does but as far as I know it depends on the conc. and temperature, for the dilute cold one it will form the Tl(III)sulfate, for hot conc. it will form Tl(I)Sulfate + Oxygen

pantone159 - 6-1-2017 at 15:28

Does elemental Tl dissolve easily in mineral acids? I have a surplus gram of it that could be good for experiments, but no Tl salts.


diddi - 6-1-2017 at 16:22

yes. it is very rective and oxidises easily in air (goes golden-grey in seconds, then all sorts of odd colours due to various oxides etc - see stock photo of poorly stored Tl)

thallium.jpg - 36kB