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Author: Subject: Chloroform -> Formic Acid
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[*] posted on 18-10-2011 at 07:12


You may be unlucky living in Australia, there are quite a few in the UK

http://www.boots.com/en/Ataka-Bath-Stain-Remover-Kettle-Desc...
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[*] posted on 18-10-2011 at 07:20


Quote: Originally posted by ScienceSquirrel  
You may be unlucky living in Australia, there are quite a few in the UK

Yeah but i dont know what country msds's i was checking... i just googled descaler msds and clicked on heaps to check

Quote: Originally posted by ScienceSquirrel  

http://www.boots.com/en/Ataka-Bath-Stain-Remover-Kettle-Desc...


Thats really cheap :O about $3 Australian or a bit more, if it was here it would be about 10-20 dollars ><




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[*] posted on 18-10-2011 at 07:23


Quote: Originally posted by Chemistry Alchemist  
The next step is Dissolving 39.99 grams of Sodium Hydroxide in Some Ethanol and adding it to the 119.37 grams of Chloroform, This will produce 68.00 grams of Sodium Formate and 58.44 grams of Sodium Chloride. How would you separate the Sodium Chloride from the Sodium Formate?
Also, would this reaction proceed on its own or would i have to heat or reflux it for it to proceed?

CHCl3 + 4NaOH → HCOONa + 3NaCl + 2H2O

What is the reference for the above?
I believe the expected main product under such conditions would be triethyl ortoformate. I really can't see how you could get sodium formate as the main product from such a reaction. The concentrated NaOH/EtOH solution is about 12% at which point there is enough ethanol for the ethoxide being in excess over the hydroxide. Some formate would certainly form, but I highly doubt it would be the main product, particularly since the third chlorine gets substituted by the solvent under diffusion control (SN1 substitution) so you don't even get the benefit of statistics.

PS: When writing equations of reactions proceeding in reactive solvents you need to include the solvent! Else, it is like a bird flying in vacuum.




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[*] posted on 18-10-2011 at 07:31


The reference is: http://en.wikipedia.org/wiki/Sodium_formate

Correct me if im wrong but if the solvent is in the equation, it wouldnt change and it would be the same on the right side as on the left... if u know what i mean...




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[*] posted on 18-10-2011 at 07:31


formates for some reason are not available otc in australia, afaik, i have always found this odd, didn't reaslise you were australian earlier. i assume it's related to the poisons scheduling that is very harsh on methanol, and this was analogously transposed to formic acid and its salts. We haven't had a methanol poisioning of note here for some time (i'm in distilling), although last week a australian lass in Bali was evacuated from said island with severe methanol poisioning from a sugar cane punch. Her mother didn't fee like drinking so the daughter drank the entire jug, was 4.1 ethanol:methanol.
if anyone knows of an australia product based on a formate please post concerning it. Our descalers tend to be sulphamic acid or as mr chem ac stated HCl or Phosphoric. Oxalic acid acid is sold everywhere neat as well, for cleaning rust.




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[*] posted on 18-10-2011 at 08:05


Quote: Originally posted by Chemistry Alchemist  
The reference is: http://en.wikipedia.org/wiki/Sodium_formate

Correct me if im wrong but if the solvent is in the equation, it wouldnt change and it would be the same on the right side as on the left... if u know what i mean...

There is no reference for that Wikipedia claim. It is just as relevant as me saying that pigs fly. They do when on an airplane, but it is not the same. Similarly, chloroform can give a formate salt, but in ethanol the reaction might or might not be preparatively reasonable (meaning that formate might not be the main reaction product!). Alternatively, it might also give formates if using ethanol only as a cosolvent for NaOH(aq), which is a possibility given that the equation is unrepresentative of the reaction. But all this is not the same, just like the pigs flying in an airplane are not the same species of pigs flying with wings. And that is why you need to include ethanol in the equation. An equation not listing all the species partaking the reaction is no reasonable chemical equation. When you write the left side of the reaction correctly, you at least have a chance to have the right side of the reaction also approximately correct.

Let me give you an exaggerated example, for the sake of illustration. Let's say you are preparing t-butyl acetate from acetyl chloride and t-butanol in an ice bath and using isopropanol as a solvent to dissolve the otherwise solid t-butanol. How would you write the equation of this reaction? (there is actually more than one level of complexity in this example!) Also: What are the products? Is the addition order important? Do the conditions matter? Can the stirring rate influence the reaction products? Does the reaction size matter? And so on... If you do this as a homework you might understand why equations like that Wiki's one are totally misleading.




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[*] posted on 18-10-2011 at 08:30


Quote: Originally posted by Nicodem  

Let me give you an exaggerated example, for the sake of illustration. Let's say you are preparing t-butyl acetate from acetyl chloride and t-butanol in an ice bath and using isopropanol as a solvent to dissolve the otherwise solid t-butanol. How would you write the equation of this reaction? (there is actually more than one level of complexity in this example!) Also: What are the products? Is the addition order important? Do the conditions matter? Can the stirring rate influence the reaction products? Does the reaction size matter? And so on... If you do this as a homework you might understand why equations like that Wiki's one are totally misleading.


Did u want me to try work it out?


[Edited on 18-10-2011 by Chemistry Alchemist]




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[*] posted on 18-10-2011 at 22:04


Why not make it just from oxalic acid and glycerol? Much simpler..

Oxalic acid is OTC in most places and even if dont, you can make it from sawdust and NaOH or from sugar/HNO3..

http://www.homechemistry.org/view/Preparation_of_formic_acid

http://web.archive.org/web/20080424022524/http://www.frogfot...





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[*] posted on 19-10-2011 at 00:51


How can it be made from Sawdust and NaOH? i have alot of both...



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[*] posted on 19-10-2011 at 01:17


Quote: Originally posted by Chemistry Alchemist  
How can it be made from Sawdust and NaOH? i have alot of both...


Very messy, dangerous and gives a product that needs somewhat heavy purification.. If you still want, good luck! Tried myself on minor scale and the yield wasnt great..

Look the papers attached by not_important in the end of first page of this thread:

http://www.sciencemadness.org/talk/viewthread.php?tid=8912

If you want a elegant route.. See this:

http://www.sciencemadness.org/talk/viewthread.php?tid=12832






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[*] posted on 19-10-2011 at 01:32


ahh i see... yeah maybbe it is a bit hard to make.... i really do wanna get into organic chemistry but i dont have the right equipment and chemicals :(



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[*] posted on 20-10-2011 at 17:13


For those curious about references that might or might not back up the claim in Wikipedia, I would suggest looking up Watts' Chemical Encyclopedia on Google Books. It gives further (even hoarier) references to works by Regnault and other early experimenters. But it does not look too promising, preparatively: apparently KOH, ethanol and chloroform will give you formic acid (and KCl, and gunk)... if heated to 100C for a week in a closed tube. Boiling alkali in aqueous solution with chloroform supposedly does nothing.
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[*] posted on 1-11-2011 at 14:27


The other possibility for getting formic acid is the electrolytic reduction of sodium bicarbonate in a partitioned cell over a Hg or Pb cathode. (It also works with sodium carbonate and even bubbling in CO2 will give some formic acid.) The method never got a lot of attention since, at that time, cyanides were easier to make than ammonia, and all the ammonia was derived from NaCN (bring it to red heat, pump in superheated steam and collect the ammonia. Sodium formate was the by-product and not exactly in short supply).

Other, more esoteric methods involved the use of glow discharges that likewise produced formic acid and several other interesting end products, though this is a good deal less easy to pull off. (Requires high voltages and vacuum techniques. Though it does explain why CO2 lasers are never sealed systems: you need to take 'em apart regularly to clean out the organic crud that accumulates.)

Electrolytic methods got a lot of attention during the first two decades of the 20th century, and the relevant texts were written by Bertram Blount and others. They fell out of interest, as newer industrial methods were developed as a result of WW I. They still work, and if you're not looking to make tons of the stuff, it's worth considering. A helluvalot less messy than trying to use some version of the haloform reaction if it's not chloroform you're after.

So far as reacting CHCl3 with hydroxides, that only works well if the "chloroform" is a side chain on a benzene ring, such as a,a,a trichlorotoluene.
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[*] posted on 1-11-2011 at 17:09


Quote:
that only works well if the "chloroform" is a side chain on a benzene ring


Doesn't have to be a benzene ring. Chloretone/chlorobutanol is pretty readily hydrolyzed (apparently to hydroxy-tert-butyric-acid) by base... also I recall one of our members synthesizing hexachloropropene from unsym-heptachloropropane, again the CCl3 was attacked by Ca(OH)2. Seems like attaching just about any group of carbon atoms to the -CCl3 will destabilize it.
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[*] posted on 5-4-2012 at 18:21
sodium formate from chloroform


i have gained a broad collection of sodium salts being that it is one of my favorite elements all of which ive made myself except sodium formate and through several of the different posts of chloroform i saw that if you mix chloroform with sodium hydroxide it will form the formate and i have search on google and here but nothing on this specific synthesis shows up. so my question is could i take the dirty undistilled chloroform(as i dont have a distillation kit yet :( ) from the reaction of bleach and acetone and mix it with NaOH will i get sodium formate or will several salts form? also any interesting reactions with sodium formate would be helpful other than the obvious creation of formic acid.
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[*] posted on 6-4-2012 at 07:28
chloroform


Quote: Originally posted by Chemistry Alchemist  
I may or may not be planning on doing this reaction, im just considering what additional steps should be taken then doing this reaction AKA Heating, reflux, distillation... this is the steps and what i think would have to be done

The first step is reacting 74.44 grams of Bleach with 58.07 grams of Acetone, this will make 119.37 Grams of Chloroform with a few by products... im guessing you just mix them together and keep it cool to let the 2 layers separate... the Chloroform layer at the bottom and the Sodium Acetate and Hydroxide layer up the top

NaClO + C3H6O → CHCl3 + 2 NaOH + CH3COONa

The next step is Dissolving 39.99 grams of Sodium Hydroxide in Some Ethanol and adding it to the 119.37 grams of Chloroform, This will produce 68.00 grams of Sodium Formate and 58.44 grams of Sodium Chloride. How would you separate the Sodium Chloride from the Sodium Formate?
Also, would this reaction proceed on its own or would i have to heat or reflux it for it to proceed?

CHCl3 + 4NaOH → HCOONa + 3NaCl + 2H2O

The last step once the 68.00 grams of Sodium Formate is isolated, it is then reacted with 98 grams of Sulfuric Acid, This will produce 46.02 grams of Formic Acid along with 142.04 grams of Sodium Sulfate. Now my last question would be How would i separate the Formic Acid from the sodium Sulfate?

HCOONa + H2SO4 → CH2O2 + Na2SO4

Does this sound about right? Please do correct me if im wrong :) and if this thread belongs in Beginners and not here then feel free to move it :)

I make chloroform all the time by just placing a gallon of bleach in the freezer for 6 hours, then remove from freezer and drain off 150 ml, relace with 150 ml acetone, shake well for several minutes. Place outside for 14 hours with top loose on the jug. After 14 hours drain salt water from jug and chloroform is in the last two cups coming out of the jug. Place these two cups in a separatory funnel and remove chloroform, add 5 ml pure ethanol to stabilize and store in a air tight amber glass container. DONE AND SIMPLE
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[*] posted on 9-4-2012 at 07:09


Quote: Originally posted by Aqua_Fortis_100%  
Why not make it just from oxalic acid and glycerol? Much simpler..

Oxalic acid is OTC in most places and even if dont, you can make it from sawdust and NaOH or from sugar/HNO3..

http://www.homechemistry.org/view/Preparation_of_formic_acid

http://web.archive.org/web/20080424022524/http://www.frogfot...


Oxalic Acid is in Mrs. Stewart's Liquid Bluing.
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