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bahamuth
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[*] posted on 29-9-2010 at 13:45


Blue compound from nitration attempt of isopentanol or n-pentanol.

Several years ago I tried to nitrate isopentanol, or n-pentanol with nitric acid and sulfuric acid and remember I got a beautiful blue compound in solution, no attempts were done to try to isolate this.

Of what i think I remember I had the nitric acid mixed with the pentanol with stirring and added sulfuric acid WAY to quick, scorching and boiling of the mix followed, and then it took on a deep but clear blue color.

IIRC I found something on the net then of a blue short chain nitroso compound that maybe was the culprit that formed under such conditions.

So my question is, do anyone know what it maybe was?




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[*] posted on 29-9-2010 at 17:22


Which was it, iso or n-pentanol? I do recall reading of some secondary pseudonitrosite or nitroles or something that are blue.

The pseudo-nitrols, RR':C(NO)(NO 2), may be obtained by the action of nitrous acid on the secondary nitroparaffins; by the action of silver nitrite on such bromnitrosoparaffins as contain the bromine and the nitroso group united to the same carbon atom (0. Piloty, Ber., 1902, 35, p. 3 0 93); and by the action of nitrogen peroxide on ethereal solutions of ketoximes (R. Scholl, Ber., 1888, 21, p. 508; G. Born, Ber. 1896, 2 9, p. 93). They exhibit an intense blue colour when in the liquid condition or dissolved in alkali and possess a very sharp smell. On oxidation with chromic acid they yield dinitrohydrocarbons, and on reduction with hydroxylamine (in alkaline solution) or with potassium sulphydrate give ketoximes, RR': C: NOH (R. Scholl and K. Landsteiner, Ber., 1896, 29, p. 87).

Perhaps some nitrous acid was formed to cause this reaction with the ketone also formed?

[Edited on 30-9-2010 by stygian]
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Rogeryermaw
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[*] posted on 29-9-2010 at 18:45


does freezing your benzene negatively affect it? i store most of my volatiles in a refrigerator and i guess it was a bit too low...



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bahamuth
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[*] posted on 30-9-2010 at 10:28


Quote:
Originally posted by stygian

Which was it, iso or n-pentanol? I do recall reading of some secondary pseudonitrosite or nitroles or something that are blue.


Think it was iso-pentanol, but as I vaguely mentioned earlier, do not really remember...

Never tried to reproduce that peculiar reaction but could give it a try, as I now have an idea of what it might be...




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[*] posted on 3-10-2010 at 08:29


I'm planning a titration against molar H2SO4 to find out the concentration of an ammonia solution.
According to Wiki, Phenolphthalein should be used for strong acid / strong base neutralisations. Both Phenolphthalein and an indicator called Neutral Red are available from eBay. Whilst the former changes colour around pH 8.3-10, Neutral Red changes between 6.8 and 8, suggesting it would be more accurate.
Which would be better to use?
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[*] posted on 3-10-2010 at 11:15


H2SO4 has two protons, the titration end point will depend on if you intent to titrate to bisulfate or sulfate. Ammonium sulfate when dilute has a pH around 5.5 or so, the bisulfate obviously is lower.

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[*] posted on 3-10-2010 at 16:39


Does anyone have experience using aqueous sodium metabisulfite to remove free iodine from compounds? I know sodium thiosulfate is often used for this purpose but I don't have any so I was wondering if I could use sodium metabisulfite. I tested it by several milliliters of aqueous sodium metabisulfite to some methanol with a pellet of iodine and it completely neutralized the color. Is there any reason why it would be a poor choice?

On a separate note, can welding gas be used as an inert gas in reactions of it is comprised of 75% argon 25% CO2? I am most concerned about the CO2, I realize I *might* be able to scrub it with NaOH or KOH but is this necessary?

[Edited on 4-10-2010 by crazyboy]




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[*] posted on 3-10-2010 at 21:53
Oxygen Tanks


Will welding gas suppliers fill rusty oxygen tanks? Pic of tanks in question attached.

@crazyboy: metabisulfite will work fine. About the inert gas, CO2 really limits the reactions that you can use the inert gas for. It seems you have overcome the hurdle of obtaining a regulator and tank, can you not find a place that will fill with N2? As i recall both use the same regulator.

pic.jpg - 7kB

[Edited on 10-4-2010 by smuv]




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Rogeryermaw
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[*] posted on 4-10-2010 at 00:06


Quote: Originally posted by smuv  
Will welding gas suppliers fill rusty oxygen tanks? Pic of tanks in question attached.
[Edited on 10-4-2010 by smuv]


in my experience they will fill a tank as long as it is certified and within the certification date barring any obvious physical damage.




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watson.fawkes
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[*] posted on 4-10-2010 at 07:49


Quote: Originally posted by Rogeryermaw  
in my experience they will fill a tank as long as it is certified and within the certification date barring any obvious physical damage.
Agreed. I want to add that there do exist companies that will do hydrostatic tests on privately-owned cylinders. Mostly this is done in-house by the big gas suppliers (e.g. Praxair), but they don't have a completely exclusive lock on that service.
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[*] posted on 4-10-2010 at 15:53


Quote: Originally posted by smuv  

It seems you have overcome the hurdle of obtaining a regulator and tank, can you not find a place that will fill with N2? As i recall both use the same regulator.
[Edited on 10-4-2010 by smuv]


Unfortunately, no. The tank contains shielding gas for welding, and while I could get it filled with pure nitrogen or argon, I wouldn't be able to use it for welding.




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[*] posted on 4-10-2010 at 16:55


Sorry this isn't chemistry related but I didn't know where else to place it and did not want to start a new thread.

Does anyone have a good link for old newspapers?

I wish to read a few from the day of my birth but haven't come across anyplace that has them online yet, so if you know of any online microfilm so to speak could you shoot me a link please, Thanks.





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[*] posted on 5-10-2010 at 04:07


Silly question. Is it possible to make hexamine perchlorate from hexamine and NH4ClO4
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[*] posted on 5-10-2010 at 07:40


Quote: Originally posted by crazyboy  

Unfortunately, no. The tank contains shielding gas for welding, and while I could get it filled with pure nitrogen or argon, I wouldn't be able to use it for welding.


I know welding gas suppliers sell argon/helium mixes. If you can use this for the welding you do and chemistry, it would be a good compromise, but filling the tank will be a bit more expensive.




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[*] posted on 5-10-2010 at 11:52


Does anyone know if 5-hydroxyvanillin has a distinct odor?
The reason why I ask is I attempted the hydrolysis of 5-bromovanillin and the end product which is crystallizing from ethyl acetate has an odor similar to vanillin (which it is contaminated with).



So after crystallizing from ethyl acetate the suppose-ed hydroxyvanillin was removed from the flask and placed into a small glass dish, the flask was rinsed with 2x5ml of dcm which was then poured into the glass dish. Only some of the material dissolved in the dcm. Next I waited for the dcm to evaporate, and I was rewarded with two distinct crystalline masses. The first being flaky cream colored crystals which seemed to be less soluble in dcm, and the second being sticky yellow crystals which were stuck to the side of the dish. The odor is a pleasant one kind of like a cross between vanilla and bubblegum.The mass of the two combine was 1.83gr from 2.00gr of bromovanillin

thanks

[Edited on 6-10-2010 by mnick12]
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[*] posted on 6-10-2010 at 21:19


How would one approach trying to separate an azeotropic mixture of Toluene/Methyl Ethyl Ketone, my goal is to completely separate and purify the existing Toluene.

The components exist as - 430g Toluene: 410g MEK.

Thank you for your assistance, I have tried the search engine with little success.
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[*] posted on 6-10-2010 at 22:45


Quote: Originally posted by mewrox99  
Silly question. Is it possible to make hexamine perchlorate from hexamine and NH4ClO4
Is hexamine a stronger base than NH3? I don't think so. So, I do not expect this to work. The only thing is that NH3 is a gas and that may be advantageous for you, but I definitely do not expect a smooth reaction in which hexamine reacts with NH4ClO4 while NH3 escapes from the mix.

Something you could try is making the sulfate salt of hexamine (does that work, I don't know, try it) and mix a solution of that with a solution of NH4ClO4. Many perchlorates of large cations have low solubility and could be precipitated out.

All of what I have written above is not well-proven, it is just some educated guessing, but you could give it a try.




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[*] posted on 7-10-2010 at 00:59


Found an ancient thread from 2002. This guy mixes HCl with NH4ClO4 and reacts hexamine with it. A precipitate forms that is highly flammable.


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[*] posted on 7-10-2010 at 11:42


Yeah I have made the suppose-ed hexamine perchlorate, when I made it was a fluffy white material which upon contact with fire burned with a luminous blue-ish flame. The smoke was rather nasty lots HCl, and kinda stinky. I did this a few years ago and if I remember correctly I used NaClO4 and HCl to generate perchloric acid, but I'm not sure it could have been NH4ClO4 and HNO3. I also made urea perchlorate in a similar manner its kinda boring stuff, in my opionion it is about as interesting as urea nitrate.
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[*] posted on 7-10-2010 at 16:13


Quote: Originally posted by Pope  
How would one approach trying to separate an azeotropic mixture of Toluene/Methyl Ethyl Ketone, my goal is to completely separate and purify the existing Toluene.

The components exist as - 430g Toluene: 410g MEK.

Thank you for your assistance, I have tried the search engine with little success.


Sodium Metabisulfite will form a complex precipitating the MEK as an adduct. Repeated washes of the MeBn with Bisulfite solution should clear up your problem.





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[*] posted on 7-10-2010 at 17:45


Hello,

Can anyone tell me how to make Aqua Regia.
I have been unable to find a definate answer with some saying it is 3:1 molar or 4:1 by weigh of 'concentrated' HCl and 'concentrate' Nitric acid.
They never specify what concentrated Nitric means and I gather it means the 70% stuff and not the 100% stuff. Also when moles of 'concentrate' HCl are being referred to does it mean actual moles of HCl (one mole = 36.45 grams) and you must use the appropriate amount of 36% solution-in-water of HCl or do you go with one mole of the actual solution in water (molecular weight I will have to figure out.

What ratio (by weight or volume) of 70% Nitric acid 37% Hydrochloric acid?
Or do you need 100% Nitric acid?

TIA,
Dann2
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[*] posted on 8-10-2010 at 00:43


Quote: Originally posted by dann2  
Hello,

Can anyone tell me how to make Aqua Regia.
I have been unable to find a definate answer with some saying it is 3:1 molar or 4:1 by weigh of 'concentrated' HCl and 'concentrate' Nitric acid.
They never specify what concentrated Nitric means and I gather it means the 70% stuff and not the 100% stuff. Also when moles of 'concentrate' HCl are being referred to does it mean actual moles of HCl (one mole = 36.45 grams) and you must use the appropriate amount of 36% solution-in-water of HCl or do you go with one mole of the actual solution in water (molecular weight I will have to figure out.


What ratio (by weight or volume) of 70% Nitric acid 37% Hydrochloric acid?
Or do you need 100% Nitric acid?

TIA,
Dann2


Aqua Regia does not need to be made perfectly, any mix of conc nitric and hydrochloric acids will dissolve Au and Pt to some extent.

The perfect mix, as you say however, is 3:1, conc (36%) HCl to conc Nitric (70%) and the ratio is done by the solution in water, nothing to do with moles, eg, 30ml HCl:10ml Nitric.

[Edited on 8-10-2010 by Picric-A]
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dann2
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[*] posted on 8-10-2010 at 11:53


Thanks for reply.
I am dissolving Bismuth to make BiCl3:2H2O
Simply dissolve Bi metal and evaporate to obtain BiCl3.
Is it fair to assum that all Nitrate will evaporate (go away) and leave the Chloride?
Thats why I though I might need to get the ratio (of HCl to Nitric) close to correct.

Dann2
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[*] posted on 8-10-2010 at 22:59


Quote: Originally posted by dann2  
Thanks for reply.
I am dissolving Bismuth to make BiCl3:2H2O
Simply dissolve Bi metal and evaporate to obtain BiCl3.
Is it fair to assum that all Nitrate will evaporate (go away) and leave the Chloride?
Thats why I though I might need to get the ratio (of HCl to Nitric) close to correct.

Dann2


As long as you keep to the 3:1 ratio (maybe add a little bit extra HCl to be sure) no nitrate will form as it is completly consumed according to;
HNO3 + 3 HCl → NOCl + 2 H2O + Cl2
You will only be left with the chloride.
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[*] posted on 13-10-2010 at 06:25


what is this compound called without the double bond between c1-c2

alpha-methyl cinnamaldehyde




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[Edited on 13-10-2010 by solo]




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