Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: Growing Lead iodide crystals help!
Wrecking Bereserker
Harmless
*




Posts: 25
Registered: 2-4-2019
Member Is Offline


[*] posted on 11-5-2019 at 10:05
Growing Lead iodide crystals help!


I reacted lead nitrate with postassium iodide to form lead iodide then i heated the solution to dissolve the lead iodide in water but the water just boils and spurts PbI2 all over!what should i do?
View user's profile View All Posts By User
Ubya
International Hazard
*****




Posts: 1213
Registered: 23-11-2017
Location: Rome-Italy
Member Is Offline

Mood: I'm a maddo scientisto!!!

[*] posted on 11-5-2019 at 12:22


lead iodide has a solubility of 0.41g/100ml of water at 100 °C. you need more water and to cover you vessel so you don't get lead splashes...




---------------------------------------------------------------------
feel free to correct my grammar, or any mistakes i make

If you are looking for chemicals check this out: [For Sale]300 chemicals (rare & unusual)
---------------------------------------------------------------------
View user's profile View All Posts By User
Boffis
International Hazard
*****




Posts: 1723
Registered: 1-5-2011
Member Is Offline

Mood: No Mood

[*] posted on 11-5-2019 at 12:28


You are simply boiling it too vigorously. Lead iodide dissolves quickly up to saturation but even in boiling water its solubility is only about 4g per litre. How much are you trying to dissolve? Did you measure the amounts of reactant you used? Did you mix them them in the correct Molar ratio? You will need to gives us a bit more information before we can help.

By the way excess lead nitrate depresses the solubility of lead iodide while excess potassium iodide increases it until finally no lead iodide will form at all on cooling only creamy yellow needles of a potassium lead iodide double salt.
View user's profile View All Posts By User
Sulaiman
International Hazard
*****




Posts: 3251
Registered: 8-2-2015
Location: UK ... on extended Holiday in Malaysia
Member Is Offline


[*] posted on 11-5-2019 at 12:46
@ Wrecking Bereserker


just in case ... lead iodide is a cumulative poison,
(by mechanisms unknown to me) the iodine helps the lead enter your body, even through your skin.
Poisoning is (I've read) similar to lead poisoning.
Sorry if this is old news, just thought it best to mention it.




CAUTION : Hobby Chemist, not Professional or even Amateur
View user's profile View All Posts By User
beeludwig
Harmless
*




Posts: 29
Registered: 7-5-2019
Member Is Offline


[*] posted on 11-5-2019 at 13:32


I've done this and have gotten the "golden rain" effect, I haven't tried making a larger crystal out of it although I'd like to. Wikipedia suggested making the crystals by reacting the chemicals through a permeable barrier. I tried this and it just made a mess. I haven't really tried anything else yet. Mostly because there's a limit to how much lead waste I want to make without a good way of remediating it.
View user's profile View All Posts By User
woelen
Super Administrator
*********




Posts: 7763
Registered: 20-8-2005
Location: Netherlands
Member Is Offline

Mood: interested

[*] posted on 13-5-2019 at 23:28


If you boil the liquid with PbI2, cover the beaker or test tube loosely with a paper tissue. Any vapor/gases easily pass through, but small droplets get stuck in the paper tissue. In this way you avoid exposure to lead salts.



The art of wondering makes life worth living...
Want to wonder? Look at https://woelen.homescience.net
View user's profile Visit user's homepage View All Posts By User
diddi
International Hazard
*****




Posts: 723
Registered: 23-9-2014
Location: Victoria, Australia
Member Is Offline

Mood: Fluorescent

[*] posted on 14-5-2019 at 02:41


i do not boil it. as soon as the PbI2 begins to disappear, it is hot enough.

[Edited on 14-5-2019 by diddi]




Beginning construction of periodic table display
View user's profile View All Posts By User
woelen
Super Administrator
*********




Posts: 7763
Registered: 20-8-2005
Location: Netherlands
Member Is Offline

Mood: interested

[*] posted on 14-5-2019 at 03:27


But this only happens when you have a very small amount of PbI2 in the liquid. Otherwise you certainly will keep on heating, until the liquid boils.



The art of wondering makes life worth living...
Want to wonder? Look at https://woelen.homescience.net
View user's profile Visit user's homepage View All Posts By User

  Go To Top