Sciencemadness Discussion Board

Please help me figure out how to make this solution

gtchemen - 7-6-2010 at 23:42

Hello
Im trying to make a Peracedic Acid (specifically performic acid)

The Original method
Calls for
279g H202 35%
469g Formic acid 88%

But the problem is i only have 27% h2o2 and i can obtain 90% formic acid
So i am assuming i can dry the formic useing mgso4 or something to dry it.
OR maybe take the other 8% water from h2o2 ( which is unlikely) Please dont tell me to freeze it as it doesnt work with my freezer.

Please give me some ideas on how i might go about this to balance the chart

So if i have 27% h2o2 and x% formic acid and adding
x amount for each and adding this much water would balance it out but how can i do this?.. I have limited chemistry knowledge please help me!

watson.fawkes - 8-6-2010 at 08:00

Quote: Originally posted by gtchemen  
Im trying to make a Peracedic Acid (specifically performic acid)
What application do you have for this reagent? Given that you don't have exact ingredients, how well it will perform with substitutes depends on what you want to use it for.

gtchemen - 8-6-2010 at 09:00

For epoxidation of an 2 degree carbon of alkene

the alkene calls for 300g (m.w) 162.19

my theory make the formic stronger and use the water off the h2o2 and it will balance out but i just dont know how to go about this.
thanks for your input

anyone able to help me solve this?
does this require knowledge of densities of the reagents?

[Edited on 8-6-2010 by gtchemen]

Nicodem - 8-6-2010 at 12:09

First of all there is no compound with a formula of "h2o2" or "H202". Surely you mean hydrogen peroxide which has an empirical formula of H2O2. The sign for hydrogen is H and for oxygen is O (and not h, o or zero!). Secondly, if you are not yet able to write down empiric formulas, you are not ready yet to do any experiments as it is pointless. You will not succeed in doing anything without knowing anything - though you might be able to have an undesirable accident. Thirdly, all you have to do is to recalculate the amounts to get the same stoichiometry and prepare the mixture accordingly. If you do not know what stoichiometry is, then you should not ask the questions you ask, but rather pay a visit to a library instead. Chemistry can be a dangerous hobby if you are clueless about what you are mixing together. There are textbooks for all kind of school levels, so take the ones you find appropriate for yourself and read them all.

gtchemen - 8-6-2010 at 14:10

thanks dicoderm for the indirect answer i wasnt quite looking for but it may have given me a nudge in the right direction

not_important - 8-6-2010 at 16:07

I'm going with Nicodem on this. Peracids are useful in a number of reactions, organic peroxides in general can get quite exciting and allow you to be able to observe your local emergency medical services close up and in action.

This is not baking a cake, simply following a "recipe" that is not understood can lead to everything from simple failure to get what you want, to ending up dead.


gardenvariety - 9-6-2010 at 16:40

Definitely read up on all the reactions and theory and test on the small scale, perhaps with other standard reagents to test your theory and work-up. After that, you might find you can concentrate peroxide in water by freezing.

zed - 13-6-2010 at 10:49

Just concentrate the H2O2 by removing some water by room temperature vacuum distillation...or evaporation.

90% Formic acid, versus 88% formic acid.....is not a significant difference for this reaction.

As for having limited chemistry knowledge.....get some. Take some classes, or find a mentor. There is nothing to equal hands-on tutoring. There are plenty of ways to get maimed or killed in a chem lab....And, someone with experience can show you the ropes, thereby increasing your chances for survival.

Dicoderm? Grrrrr.