ldanielrosa
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lead acetate
I synthesized some lead acetate out of curiosity and to make a control solution for lead detection.
I don't have all the information I'd like. It appears to have three hydration states (wikipedia), and a low melting point in two of them. I put my
product in a desiccator for a few weeks with NaOH, but I don't know if this will take it to trihydrate or annhydrous.
Is there a simple way to determine the hydration state without melting it? More importantly (to me anyway) is there a simple way to arrive at
trihydrate?
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Retard-3000
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where wikipedia says that the melting point of the trihydrate is 75C that doesn't mean that it'll be molten at 75C it just refers the temperature at
which it'll lose the 3 water molecules bonded to it. the best way to calculate what hydrate it is, measure out a sample of the lead acetate, then heat
to 100C to ensure you drive off all the water, then reweigh the lead acetate and from there just a few calculations and you'll know the hydrate of it.
EDIT: 0.01 mole of anhydrous lead acetate = 3.253g
0.01 mole of lead acetate trihydrate = 3.793g
from this a simple way to test if it's lead acetate trihydrate, simply weigh out 3.79g and heat it to 75C+, and then reweigh it, if it's 3.253g +-
0.1g then it's the trihydrate.
[Edited on 23-1-2011 by Retard-3000]
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gsd
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If you crystallize out lead acetate from water solution what you will get is trihydrate.
You can safely dry it out without decomposition up to about 40 Deg C.
Also you should avoid its prolonged exposure to air as it tends to absorb CO2 from air and that spoils its solubility. A good quality Lead Acetate -
trihydrate should give water white solution in distilled water.
gsd
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dann2
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See the Lead Salts thread:
http://www.sciencemadness.org/talk/viewthread.php?tid=5490
May be useful
Dann2
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