beastmaster
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ammonium formate
I have ammonium chloride and formic acid. I would like to make a small amount of ammonium formate. Could I make NH3 by adding my NH4cl to naoh and
bubbling the gas into the formic acid, then evaporate off the remaining formic acid? Iv'e searched on the web and my few chem. books in my collection
for a preparation but haven't had no luck. Any Info or a shove in the right direction to where to find a lab preparation would be of great help.
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not_important
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Yeah, that would work. Better to drip a strong NaOH solution onto the NH4Cl in a flask, so as to be able to control the reaction rate. Also watch
out for suckback of the formic acid into the ammonia delivery tube; check out descriptions of making aqueous ammonia or hydrochloric acid from the
gases. You might start off with the delivery tube just touching the acid and a slow rate of ammonia generation; stir the acid during the addition
process.
As formic acid is pretty strong, you could get away using Na2CO3 instead of NaOH, using a _wide_ delivery tube and heating the NH4Cl+Na2CO3 80-100 C.
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DJF90
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The way I've seen bubbling HCl into water described is with an inverted funnel. This would be applicable here, and would probably be much better than
a wide delivery tube.
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not_important
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Wide tube was if Na2CO3 was used instead of NaOH, the ammonium carbonates might clog a narrow tube but are advantageous for folk who have difficulties
getting NaOH - no sense wasting it on making ammonia.
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DJF90
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Sorry I didnt read it properly. Using an inverted funnel would help reduce the suckback greatly if gaseous ammonia is bubbled directly into the formic
acid.
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S.C. Wack
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Given that you'd need 594 liters of ammonia to convert a liter of 100% formic acid to ammonium formate, if you're having suckback problems what you
really need to do is increase the gas flow, unless you have nothing better to do for the rest of the week.
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