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Lithium C/wk HELP!

Right, first off, I know there are about fifty of these threads, but none of them told me what I want to know.

Here's the deal: Through two procedures, I had to determine the Ar of a given mass of Lithium, reacting it with water to produce 100cm6^3 of LiOH. Then I had to titrate this with 0.1mol dm^-3 HCl acid. The procedure I was fine with, and I was fine with the calculations too - they're all sorted, even the erros of measurement are done.

What I'm having trouble with, is finding ways to imrpove the procedural erros in the experiment which are as follows:

-The top-pan balance reads only to 0.01dp.
SOLUTION - Use an analytical balance, that reads to 0.001dp. (Sorted).

-Gass loss, between adding Li to H2O and placing bung in conical side-arm flask.
SOLUTION - Minimize human error: hold bung as close as possible to flask, or get someone else to put it on, reducing reaction time.

-Li isn't pure - forms LiO rapidly in air after Paraffin is cut from the outside.

Can anyone please tell me how to reduce this error? :confused: I thought that maybe conductiong this part of the experiment in an inert atmosphere, for example, in a chamber where a vacuum can be created, and only gloved hands hanve to enter the chamber. But Ihaven't got a clue if this is feasible, or what those chambers are called!!! This assignment HAS to be finished tomorrow or the day after, so I'm in desperate need of help!!

:s-smilie: :frown:
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oceane
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LabRat99

-Li isn't pure - forms LiO rapidly in air after Paraffin is cut from the outside.

Can anyone please tell me how to reduce this error? :confused: I thought that maybe conductiong this part of the experiment in an inert atmosphere, for example, in a chamber where a vacuum can be created, and only gloved hands hanve to enter the chamber. But Ihaven't got a clue if this is feasible, or what those chambers are called!!! This assignment HAS to be finished tomorrow or the day after, so I'm in desperate need of help!!



In labs some experiments are run under nitrogen to avoid oxidation but in a school lab I guess maybe what they're looking for is that the Lithium needs to be stored in oil. When you take a piece out to cut it, there will still be a film of oil around it.
Yeah, that's one of the errors too, but thank you so much!!!! Even though I did it this morning, but never mind. Still, I really appreciate your help.

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