nannah
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Recrystallize sodium benzoate with ammonia?
Hi, guys. Yesterday when i was grocery shopping with the family i found that they sold many different interesting chemicals. For example they had
sodium benzoate of unknown purity that i want to start out purifying.
Wikipedia say that its soulable in liquid ammonia and pyridine. I dont have any pyridine, but i do have some old 25% strength ammonia.
Can recrystallize sodium benzoate with 25% ammonia you think?
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blogfast25
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Quote: Originally posted by nannah  | Wikipedia say that its soulable in liquid ammonia and pyridine. I dont have any pyridine, but i do have some old 25% strength ammonia.
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By 'liquid ammonia' is meant just that: pure, liquid ammonia (boiling point - 33.3 C), not a 25 % solution of ammonia in water.
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unionised
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Why not just use water?
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blogfast25
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Its temperature-solubility curve is very flat. Of course you could boil down from a saturate solution.
[Edited on 5-10-2014 by blogfast25]
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aga
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A quick Wiki search says it doesn't even Melt until 410 C, so heat it up a lot and any organics will boil away way before that temperature.
Have you researched what contaminants Might be in there ?
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DraconicAcid
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Dissolve it in water, add hydrochloric acid to give benzoic acid. This recrystallizes very nicely from water, and then you can make sodium benzoate
by reacting it with baking soda.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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S.C. Wack
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The internet gives away many interesting chemical books such as Purification of Laboratory Chemicals...now up to the 7th ed as time marches on.
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blogfast25
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| Quote: Originally posted by DraconicAcid | | Dissolve it in water, add hydrochloric acid to give benzoic acid. This recrystallizes very nicely from water, and then you can make sodium benzoate
by reacting it with baking soda. |
Thereby reintroducing impurities from the baking soda!  Like 'rice powder'
anti-caking agent, for instance.
Get a chemical grade sodium bicarbonate instead.
[Edited on 6-10-2014 by blogfast25]
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