Sciencemadness Discussion Board - The short questions thread (3)

The short questions thread (3)

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CHRIS25 - 4-4-2013 at 02:06

How does one test for the presence of ammonium in Ferrous ammonium sulphate? Suspecting that upon crystalization I have only ferrous sulphate.

The latter I also made and it is the exact same colour as my supposed ferrous ammonium sulphate, although I have extremely large crystals from the Ferrous ammonium Sulphate, I know that as I was neutralizing the ammonia solution with H2SO4 i went past the neutralisation stage and so brought it back with the addition of more ammonium solution. The consequences of which meant that there was no longer an equimolar amount of pre-prepared ferrous sulphate mixing with the ammonium sulphate. Thankyou.

DraconicAcid - 4-4-2013 at 07:58

Quote: Originally posted by CHRIS25

How does one test for the presence of ammonium in Ferrous ammonium sulphate? Suspecting that upon crystalization I have only ferrous sulphate.

Place a small amount of it into a small beaker. Dampen a piece of litmus paper and stick it to a watch glass and set it on the beaker. Add sodium hydroxide solution to your solid material. If ammonium is present, it will be converted to ammonia, which will turn the paper blue.

confused - 4-4-2013 at 10:08

how badly would a round bottom flask be stressed if it was heated directly on a hotplate without an oil bath to about 300°C+?

Mailinmypocket - 4-4-2013 at 10:41

Quote: Originally posted by confused

how badly would a round bottom flask be stressed if it was heated directly on a hotplate without an oil bath to about 300°C+?

I often use air baths with foil skirts to heat flasks on a hot plate around that temperature, no problem. Don't let the RBF touch the hotplate-that might cause stress.

Pyro - 4-4-2013 at 10:42

depends on the quality of the flask, if the bottom is touching the hotplate, if you have wrapped Al foil around the top to catch the heat.
personally I think you will never get the flask up to 300*C without an oil bath

BobD1001 - 4-4-2013 at 20:01

Could anyone say if the following bottle be okay for storage of Concentrated Nitric acid?

http://www.amazon.com/Wheaton-Capacity-Polypropylene-Polyeth...

Would there be concern of pressure buildup from concentrated nitric, and would an amber reagent bottle with a glass stopper better suit my needs?

Thank you

confused - 4-4-2013 at 20:30

should be ok for nitric acid...not sure about the pressure though, where are you storing it and what concentration is it in?

BobD1001 - 4-4-2013 at 21:21

Quote: Originally posted by BobD1001

Could anyone say if the following bottle be okay for storage of Concentrated Nitric acid?

http://www.amazon.com/Wheaton-Capacity-Polypropylene-Polyeth...

Would there be concern of pressure buildup from concentrated nitric, and would an amber reagent bottle with a glass stopper better suit my needs?

Thank you

To Add:

The concentrated nitric acid will be produced by vacuum distillation, so likely in the neighborhood of 90%+. It will be stored at ambient temperature as I do not have a lab freezer, this ambient temperature will be a relatively constant approximately 21 degrees C.

[Edited on 5-4-2013 by BobD1001]

CHRIS25 - 5-4-2013 at 04:51

Quote: Originally posted by DraconicAcid

Quote: Originally posted by CHRIS25

How does one test for the presence of ammonium in Ferrous ammonium sulphate? Suspecting that upon crystalization I have only ferrous sulphate.

Thankyou, or basically do as you suggest but could stick the litmus directly to the inside of the beaker near the top, will try anyway.

Pyro - 5-4-2013 at 05:32

you should get the type with the aluminium lining. the Al will passivate and won't let it through the cap.

confused - 7-4-2013 at 07:31

but doesn't the PTFE liner prevent nitric acid fumesfrom passing through the cap?

confused - 7-4-2013 at 07:35

im trying to obtain some mercury metal would a mercury tilt switch or mercury thermometer contain more mercury?
(i know it's a waste of perfectly great thermometers but those are the only 2 sources a can get mercury in my country

)
im asuming that a thermometer with a higher temperature range would contain more mercury?

hissingnoise - 7-4-2013 at 08:10

You shouldn't assume that all tilt switches will contain elemental mercury . . .

confused - 8-4-2013 at 04:47

...wouldn't a mercury tilt swtich contain mercury?

Finnnicus - 8-4-2013 at 05:08

Question.

Good use for large amounts of Ca(OH)2?

confused - 8-4-2013 at 05:20

limewater to test for CO2?
synthesis of Sodium/Potassium hydroxide with reaction between sodium/potassium carbonate and calcium hydroxide?

Finnnicus - 8-4-2013 at 05:23

Potassium carbonate... OTC?

Edit: then I could decomp the resulting Calcium carbonate into CaO?

[Edited on 8-4-2013 by Finnnicus]

confused - 8-4-2013 at 05:25

i got mine at a store selling pottery supplies, usually used as a glaze

confused - 8-4-2013 at 05:29

possible, but that would require alot of heat above above 840 °C

Lambda-Eyde - 8-4-2013 at 09:56

Quote: Originally posted by Finnnicus

Question.

Good use for large amounts of Ca(OH)2?

Make benzene?

Finnnicus - 8-4-2013 at 15:07

Explain.

Vargouille - 8-4-2013 at 15:35

A dry distillation of Ca(OH)2 and sodium benzoate yields benzene and friends. You can find more information in the member publications, I believe.

Finnnicus - 8-4-2013 at 17:10

Lovely thank you.

Boron Trioxide - 12-4-2013 at 19:06

So I am building a magnetometer, and I need a liquid or solid that has the most hydrogen atoms per volume, does anyone know what hydrocarbon or other substance would have the most hydrogen molecules per volume that is easily obtainable.

Thanks for your help

Metacelsus - 12-4-2013 at 19:24

Water? 2 mol H atoms / 18 g ; 1 g / cm^3 = 0.111 mol H atoms / cm^3
Paraffin wax? ~2 mol H atoms / 14 g ; ~0.8 g / cm^3 = 0.114 mol H atoms / cm^3

toothpick93 - 14-4-2013 at 02:34

Could the Production of Nitric Acid be done by this reaction?

H2SO4 + 2KNO3 = K2SO4(precipit) + 2HNO3

If so does it have to be distilled? or does the K2SO4 actually precipitate out?

Finnnicus - 14-4-2013 at 02:48

You're really going to want to distill it...

toothpick93 - 14-4-2013 at 02:52

Is it possible to do it with out distilling? I dont have any sort of equipment that allows me to distill

Finnnicus - 14-4-2013 at 03:06

This doesn't sound like a good idea... But if you are all glass, i guess you could use the crude HNO3/H2SO4/K2SO4 Solution, just make sure that what ever is nitrated (assuming thats what you're doing) does not react with K2SO4. Also use an excess of H2SO4.

...someone smarter than me is needed to help this guy.

Finnnicus - 14-4-2013 at 03:08

OR! You could produce NO2 vapour and dissolve that in water. Just add copper to your crude solution and dissolve the NO2 produced?

Vargouille - 14-4-2013 at 04:48

You will produce "nitric acid", in the sense that it's a mixture of protons and nitrate. Your mixture of potassium nitrate, potassium sulfate, nitrate ions, sulfate ions, and protons will probably act like nitric acid for the most limited of purposes (e.g. some nitrations), however, the inclusion of potassium and sulfate will make it a poor source of nitric acid for most purposes, nor will the solid at the bottom of your flask be purely potassium sulfate. The way people get the nitric acid, and make the potassium nitrate react more fully, is to distill off the nitric acid. A better option, without resorting to distillation, would be to mix solutions of sulfuric acid and calcium nitrate, so that the calcium sulfate will precipitate, leaving a fairly dilute solution of nitric acid. If you need concentrated or fuming nitric acid, you really do need a distillation set up.

barley81 - 14-4-2013 at 11:43

Here is a short, fun question. What does the flame look like if you light a jet of oxygen in an atmosphere of methane (or any other fuel gas)? If the gas contains carbon, I suppose a lot of soot will be produced.

This experiment is too dangerous to try for most amateurs, as there is substantial risk of explosion.

DraconicAcid - 15-4-2013 at 11:22

Quote: Originally posted by barley81

Here is a short, fun question. What does the flame look like if you light a jet of oxygen in an atmosphere of methane (or any other fuel gas)? If the gas contains carbon, I suppose a lot of soot will be produced.

This experiment is too dangerous to try for most amateurs, as there is substantial risk of explosion.

I believe it looks exactly like a regular flame. Remson's "College Chemistry" (1904) has this an an experiment- break off the bottom of a good-sized retort, blow coal-gas in through the mouth and ignite once all the air is purged from it. Then take a platinum tube, and run oxygen through it, and pass the tube into the gas where the oxygen will catch fire.

jenifer133 - 15-4-2013 at 11:44

When equal volumes of the following pairs of liquids are mixed thoroughly and allowed to stand, which pair is most likely to separate into two layers?

Thanks

elementcollector1 - 15-4-2013 at 11:58

Quote: Originally posted by jenifer133

When equal volumes of the following pairs of liquids are mixed thoroughly and allowed to stand, which pair is most likely to separate into two layers?

Thanks

...Cleverly disguised spam? The username, lack of follow-up on the post (what pairs of liquids?) and the signature check out for spam.
If that's the case, hold on to your Faraday cages, folks, the spammers are getting smarter.

Vargouille - 15-4-2013 at 12:16

Or someone isn't very good as asking to be spoonfed, since this is almost certainly a question ripped straight from homework?

hafnium - 17-4-2013 at 00:29

Do I need a water trap if I'm using an aspirator for a vacuum distillation procedure? And if I do, would this one work?: (http://www.ebay.com/itm/24-40-inlet-Adapter-for-vacuum-trap-...).

I guess I'm really asking if water getting sucked back into the system is a real concern when vacuum distilling.

confused - 17-4-2013 at 01:08

I am completly new to vacuum distillation, i would like to know if it is possible to connect a water aspirator to the water pump supplying water to the condenser using a T joint connection to split the water imput between the condenser and the water aspirator.

What effect would that have on the stength of the vacuum and should i worry about the condenser cracking due to overpresure or not enough water flowing though it?

[Edited on 17-4-2013 by confused]

woelen - 17-4-2013 at 02:14

I see no problem with that. I usually run a very low flow of water through the cooler.

An even better optimization might be to use the water from the cooler for the water aspirator. I first would take the cooler and the water coming from the cooler then goes to the aspirator. Of course, you then need a decent flow of water through the cooler in order to have good operation of the aspirator. I never tried this myself though, I have a true vacuum pump and no need of a water aspirator. Try it with some innocuous compound before you do things with highly dangerous/corrosive chemicals.

confused - 17-4-2013 at 07:51

im concerned about the presure buildup in the water condenser possibly cracking it

Mailinmypocket - 17-4-2013 at 08:30

Are you talking about water pressure from the cooling, or negative pressure from the vacuum? Condensers can handle normal vacuum distillation pressures, they are made for it. I've never had a condenser implode or crack from vacuum distillations. Test it under vacuum without any reaction running first if you want to be extra cautious.

confused - 17-4-2013 at 21:32

no, i mean that since the water aspirator will be at the water output of the water condenser, wount it increase the pressure of the water in the condenser since the narrow opening of the water aspirator would increase the water pressure in the condenser?

elementcollector1 - 17-4-2013 at 21:39

In a similar vein as the last question, which is better for vacuum filtration (and possibly distillation): A hand pump or an aspirator? (I may have asked this before, I forget.)

Vargouille - 18-4-2013 at 01:12

It depends on the set-up in your lab. If you have a faucet in your lab with water running through it, it's great. It gives you fairly low pressures and you don't have to constantly hold it like you do with a hand pump. If you don't, like I do, it's either use the hand pump or pick up your stuff and mosey on over to a faucet. I choose the former.

hafnium - 18-4-2013 at 14:43

A hand pump would be incredibly impractical for a vacuum distillation setup, as you'd have to constantly be applying your vacuum manually. It would work far better for vacuum filtration, but even then, a water aspirator is the better choice. Aspirators are cheap as hell too (something like $20 + whatever adapters you need for your sink or hose).

Don't get a hand pump...

manimal - 19-4-2013 at 20:31

The other day I was musing on the Robinson tropinone synthesis and the reduction of 2-carboalkoxytropinones to alkyl ecgonines. The literature calls for sodium amalgam to selectively reduce the tropinone into the preferred exo orientation; would aluminum amalgam be able to achieve this same result? There are a dearth of literature references for the reduction of cyclic amino ketones by Al/Hg (the commonest reductive amalgam being sodium) and I am curious if the 'nascent hydrogen' generated would be active enough to affect this particular reduction.

Finnnicus - 23-4-2013 at 01:28

I have just (like actually, 10minutes ago) obtained ~4kg of filthy steel turnings, which I will clean, then what? I need something to do with this just sitting around... Maybe chromium extraction? I'll UTSE, but maybe something a little more interesting, and not requiring 1907 °C to get a pretty product. Any suggestions?

Calcium Carbide?

chemcam - 23-4-2013 at 16:58

Can calcium carbide be made by bubbling acetylene gas through a solution of a calcium salt? I have an acetylene tank but I want a solid from which to generate it by addition of water.

Picric acid yellow stains

CycloKnight - 27-4-2013 at 06:17

Help !
Can someone please tell me how to remove yellow picric acid stains? They've been on my kitchen linoleum floor for weeks, I've scrubbed and scrubbed. I've used lithium carbonate, but that isn't working either. I've also tried ammonia, acetic acid, detergent, ethanol, methanol, toluene, various bleaches (calcium hypochlorite, sodium hypochlorite and oxone), and a bucket load of elbow grease.

Is there anything that can remove these yellow stains?

Vargouille - 27-4-2013 at 07:56

This site has a few suggestions to clean up. Aside from the ones you've tried, there is one made from boric acid, sodium benzoate, and water (4 parts boric acid, 1 part benzoate, 100 parts water) that may work for you.

CycloKnight - 27-4-2013 at 09:37

Thanks for the suggestion, I'll be trying it soon.

Metacelsus - 27-4-2013 at 11:53

Quote: Originally posted by chemcam

Can calcium carbide be made by bubbling acetylene gas through a solution of a calcium salt? I have an acetylene tank but I want a solid from which to generate it by addition of water.

No. Think about what would happen if it did form -- it would instantly react with the water to produce acetylene.

chemcam - 27-4-2013 at 17:17

Quote: Originally posted by Cheddite Cheese

Quote: Originally posted by chemcam

Can calcium carbide be made by bubbling acetylene gas through a solution of a calcium salt? I have an acetylene tank but I want a solid from which to generate it by addition of water.

No. Think about what would happen if it did form -- it would instantly react with the water to produce acetylene.

Duh! Whoops! I mean can calcium carbide be made from acetylene in any way?

elementcollector1 - 29-4-2013 at 09:46

Don't think calcium carbide can be made from acetylene (the reaction would usually lean the other way).
Question: Can chlorine gas (and water dispersed therein) react with sulfuric acid? Chlorosulfuric acid exists, but apparently requires chlorination of sulfuric acid with PCl5.

DraconicAcid - 29-4-2013 at 09:50

Quote: Originally posted by elementcollector1

Don't think calcium carbide can be made from acetylene (the reaction would usually lean the other way).
Question: Can chlorine gas (and water dispersed therein) react with sulfuric acid? Chlorosulfuric acid exists, but apparently requires chlorination of sulfuric acid with PCl5.

I don't think so. You can react dry chlorine with SO2 to get SO2Cl2, though.

Eddygp - 1-5-2013 at 07:53

Will NH3 reduce Fe2O3?

Fenir - 7-5-2013 at 17:29

What radioisotopes would be most common in the sediment at the bottom of Chernobyl's cooling pond?

woelen - 7-5-2013 at 23:48

Quote: Originally posted by Eddygp

Will NH3 reduce Fe2O3?

No, Fe2O3 is not reduced by NH3.

Lambda-Eyde - 8-5-2013 at 00:01

Quote: Originally posted by elementcollector1

No, conc. sulfuric acid is used to dry chlorine.

Finnnicus - 9-5-2013 at 01:23

Bad tasting, non toxic, easy to make? Any suggestions?

confused - 9-5-2013 at 06:57

capsaicin extract

up to you if you want to try this but test it on yourself to make sure you dont give too much to any unsuspecting victim

Finnnicus - 9-5-2013 at 07:08

I really think thats a little too evil... Its for my cat.

Pyro - 9-5-2013 at 07:14

what's it eating?

Finnnicus - 9-5-2013 at 08:17

My cables. Ugh, sometimes they're used for high voltage, so they are super wrecked. (Not live while the cat could be near at all BTW)

I know that nail polish that tastes super bad is sold, but the key ingredient is hard to synth

[Edited on 9-5-2013 by Finnnicus]

mr.crow - 9-5-2013 at 15:35

Try "Alum" from the grocery store. Or a dollar store squirt gun with water.

Finnnicus - 9-5-2013 at 15:49

Really? Alum? I didn't know that tasted bad... Also, looking for more of a challenge than a water pistol

confused - 9-5-2013 at 16:18

or you could try one of there methods
http://www.wikihow.com/Make-Homemade-Cat-Repellent

Mailinmypocket - 9-5-2013 at 16:39

Or you could just buy this and spray your wires with a very dilute solution of it:

http://www.ebay.com/itm/110939181456?redirect=mobile

I bought some myself, and let me tell you... If it was on a wire and I still enjoyed chewing wires, I'd damn well stop! Nasty- good for pranks too

Finnnicus - 9-5-2013 at 16:59

I'm looking for something scientific, you know, home made. Maybe I'll run the "Bad Smelling Chemicals" thread through google, to check toxicity.

confused - 10-5-2013 at 04:36

what type of vacuum pump would you guys reccomend for vacuum filtration and vacuum distillation?

elementcollector1 - 10-5-2013 at 05:26

Apparently, anything will work for filtration (except for a hand pump), even vacuum cleaners. For distillation, I would honestly recommend an aspirator - no suckback or chemical traps necessary for a good plastic one.

Glucose Oxidase - 10-5-2013 at 10:28

Hello guys i was wondering if anyone can help me.
i recently started a chlorate cell but i noticed the following :
-white mush forming on the cathode (it was white with some carbon in it and made a crushing sound when pressed with a spoon and didn't react with citric or acetic acid and gave a burning feeling when put on hand)
-a brownish residue at the bottom (seen similar material during the filtration of the solution)
-transparent crystals at the bottom ( haven't tested them yet)

My cell specs are:
-4 carbon rods from a battery (3 anجodes 1 cathode)
-2.5 kg of table salt (and i am saying table salt not NaCl because i doubt the purity)
-tap water 9 liter ( known to contain high calcium content and other salts)
-computer power supply (connected the rods to 5v)
-a 10 liter container previously used to store water

please help me identifying the material i mentioned above

[Edited on 10-5-2013 by Glucose Oxidase]

Acidum - 10-5-2013 at 11:31

As for cat-chewing-cables problem, I would definitely go for capsaicin. Diluted solution of course.

Maybe it sounds a bit rough, but we use similar method for teaching dogs not to eat food of unknown origin - simply by leaving pieces of food soaked with some hot paprika (peppers) left in some places like corners or table. After couple of hearth-tearing painful screams at least You will be certain that poor thing will survive any attempts of poisoning or electrocution...

...not to tell how good lab practice extraction of capsaicin is...

chemcam - 10-5-2013 at 12:13

Quote: Originally posted by Acidum

...not to tell how good lab practice extraction of capsaicin is...

I have done the extraction numerous times and ingested plenty of pure capsaicin. When you perform the lab procedure just make sure you do not use an alcohol that has been denatured, it is likely that the denaturing chemical would be left behind, even if trace amounts I still avoid it. Go buy very high proof drinking ethanol like everclear or moonshine then purify it more or just distill your own 96%, that's what I do. If 99% is needed you can distill from a molecular sieve or similar means.

Pyro - 10-5-2013 at 12:30

remember the jar of RP/WP/H3PO4/... that I had after the fire?
I put in water, then CuSO4 to make the present WP less reactive and then filtered it. now the filter has lots of RP but also something dark brownish, certainly not RP. will RP react with CuSO4?

confused - 11-5-2013 at 10:28

Quote: Originally posted by elementcollector1

Apparently, anything will work for filtration (except for a hand pump), even vacuum cleaners. For distillation, I would honestly recommend an aspirator - no suckback or chemical traps necessary for a good plastic one.

yes, but my workarea/lab is not near a water source and rigging up my waterpump with an aspirator while maintaining water flow through the condenser while doing a distillaion isn't really feasible at the moment.

so, how powerful would a standard lab vacuum pump usually be?
and while we're at it, what unit do you guys use to calculate negative presure(vacuum)? Pa, bar, mmHg, psi or atm?

Morgan - 15-5-2013 at 06:17

Would candle wax dissolve in methanol if it were melted or would it tend to separate?

confused - 15-5-2013 at 06:54

paraffin wax is miscible in methanol,
however, the melting point of paraffin wax is really quite close to the boiling point of methanol, so you would have to continously add more methanol to prevent all of it from evapourating/boiling away unless you use a reflux setup

not to mention that methanol vapours are flamable, so, i highly reccomend using somthing other than an open flame or anything that could possibly create a spark while doing it.

out of curiosity, what would you want to do that for?

DraconicAcid - 15-5-2013 at 08:34

Quote: Originally posted by confused

Are you sure? I seem to recall finding that heptane didn't mix with methanol as well as I expected, and paraffin would be even less likely to dissolve in it.

The Merck Index says that paraffin is insoluble in water and alcohol.

Morgan - 15-5-2013 at 13:43

Quote: Originally posted by confused

paraffin wax is miscible in methanol,
however, the melting point of paraffin wax is really quite close to the boiling point of methanol, so you would have to continously add more methanol to prevent all of it from evapourating/boiling away unless you use a reflux setup

not to mention that methanol vapours are flamable, so, i highly reccomend using somthing other than an open flame or anything that could possibly create a spark while doing it.

out of curiosity, what would you want to do that for?

I was pondering the possibility of using paraffin as fuel but initially starting the engine with methanol. Methanol has some good qualities but the boiling point so low that perhaps transitioning to wax would work better in some cases. For my purposes, gasoline ruins the fuel/air ratio and becomes too rich, often so much so you can't even get the flame front to chase down into the combustion chamber. Paraffin wouldn't start evaporating until heated to a fairly "high" temperature. I'm trying to keep it simple, the engine feeding off an evaporating pool of fuel in the bottom of the combustion chamber.
I've tried other fuels and some blends - nitromethane, acetone, ether, ethanol, isopropyl, and gasoline.
The store I was at today had nitro for $30.00 a half gallon. It's kind of expensive and doesn't really work for what I do.

confused - 15-5-2013 at 16:11

Quote: Originally posted by DraconicAcid

Quote: Originally posted by confused

...my bad, i was going by the assumption that organic compounds dissolve in organic solvents

but i just checked the polarity of paraffin wax and methanol. Paraffin wax is non-polar while methanol is polar

Morgan - 15-5-2013 at 19:20

Some tidbit pertaining to some possible exceptions of solubility of "wax compounds" and alcohols.
"Ethanol has been used advantageously
as a co-solvent to modify the polarity of pressurized
carbon dioxide or water for the extraction of natural products
[6, 7]. More recently the application of hot ethanol to recover
waxes from flax fiber processing waste containing cuticle tissue
was also demonstrated [8]. These results motivated the
current investigation of the temperature-dependent solubility of fatty esters in ethanol and the possibility of use in biomassto-
ethanol conversion."
Temperature-dependent solubility of wax compounds in ethanol
http://naldc.nal.usda.gov/download/44460/PDF

electrolytic activation of iron filings

Organikum - 15-5-2013 at 22:07

Randolph Carter who I believe knows what he does speaks in this post of electrolytic preparation of purchased iron filings, which were used in a nitropropene reduction to the correspondending ketone.

Now the only "preparation" or activation of iron for such reactions I know of is the short wash in diluted HCl....
But the electrolytic sounds interesting and promising.
If I only had a clue how to do it.

Anybody in the know willing to help me out?

regards
/ORG

DraconicAcid - 16-5-2013 at 08:47

Quote: Originally posted by Morgan

Some tidbit pertaining to some possible exceptions of solubility of "wax compounds" and alcohols.
"Ethanol has been used advantageously
as a co-solvent to modify the polarity of pressurized
carbon dioxide or water for the extraction of natural products
[6, 7]. More recently the application of hot ethanol to recover
waxes from flax fiber processing waste containing cuticle tissue
was also demonstrated [8]. These results motivated the
current investigation of the temperature-dependent solubility of fatty esters in ethanol and the possibility of use in biomassto-
ethanol conversion."
Temperature-dependent solubility of wax compounds in ethanol
http://naldc.nal.usda.gov/download/44460/PDF

Interesting paper. It shows that at 45oC, the solubility of these waxes (all of them esters, not the paraffin sort) is on the order of 0.05 g/L. That's not very soluble at all.

confused - 16-5-2013 at 23:24

Hi, is there any way to make or extract sodium dodecyl sulfate from commonly avalible products
without oleum, chlrosulfuric acid or SO3?

I need some for preparation of some buffer solutions for microbiology

LiD - 22-5-2013 at 15:29

Is there any known method to turn an enamine to an enol ether? I found only references to turn them back to ketones... But I would need to get an enol ether and not get back the oxo.

Thanks!

solo - 24-5-2013 at 13:23

I would like to know how to add a methoxy group ....starting with,

.....and end up with this,

Metacelsus - 27-5-2013 at 17:41

I have a question regarding the use of MMO anodes in acidic conditions. I've been doing some work with chlorinating organic compounds using chlorine generated in situ via electrolysis, but to avoid the haloform reaction I need acidic conditions. I have been using graphite anodes, but they corrode rapidly into annoying black sludge. Will a MMO anode stand up to acidic conditions (specifically HCl)?

elementcollector1 - 27-5-2013 at 19:16

If it stands up to Cl2, I'd be willing to wager the same for HCl. Mind you, platinum or platinum-plated is where it's at.

Metacelsus - 28-5-2013 at 10:51

OK, I'm trying it now. I hope you're right!

By the way, where can you get platinum electrodes? Seems expensive.

[Edited on 28-5-2013 by Cheddite Cheese]

Organikum - 28-5-2013 at 13:36

Quote: Originally posted by confused

Quote: Originally posted by elementcollector1

In this case you want a chemical resistant diaphragm pump with PTFE heads, it is not about power but resistance and tolerance to vapors in this case. In the end it solely depends on the size of your briefcase.
There are heaps of vacuum related threads here offering all answers you might look for, pls search.

We at SCM, well at the least the real ones, measure vacuum in "s**k!" a unit which is directly derived from the english weight "stone". The detailed information is in the "over 18" section of SCM.

regards
/ORG

halogen - 31-5-2013 at 19:39

http://www.britannica.com/EBchecked/topic/17932/aluminosilic...

"Aluminosilicate glasses find applications similar to those of borosilicates, but the former can stand higher operating temperatures; glasses with relatively high alumina contents and no boric oxide are exceptionally resistant to alkalies. "

That sounds smashing, baby. Has anybody heard of it used; or why isn't it common? Just hard to melt, or another flaw?

Solo: There was a synthesis of 3-something-pyr, nicotine maybe, wherein first was brominated, then chlorinated, bromine removed. It's ugly but what else? Demethylenation? Best luck creating a special enzyme, actually, it's a long shot but some kind of hydroxylase might work!! A cactus enzyme eh? It works fa them.

[Edited on 1-6-2013 by halogen]

[Edited on 1-6-2013 by halogen]

Organikum - 1-6-2013 at 17:58

Gorilla Glass?

halogen - 1-6-2013 at 21:02

For labware though. I found some stuff: centrifuge tubes, raw tubing, it's apparently helium proof. It's not common, it can't be that much more difficult to form, looking at brittanica's mp diagram. I'd thought chemists would appreciate alkali&heat resistance.

And - this is the answer! :

"Aluminosilicate glass is very difficult to work with because it is very prone to reboil. That is, while bringing it a working temperature, the glass develops bubbles over the surface that are impossible to remove. One other challenge with aluminosilicate glass, which is different from other glasses, is that you can't clean itwith hydrofluoric acid (see Sec. 4.1.10). If attempted, it will cause the surface to develop a translucent sheen that is also impossible to remove. It is safe (for the glass) to clean the surface with nitric acid"

From http://www.scribd.com/doc/79709916/7/Different-Types-of-Glas...

[Edited on 2-6-2013 by halogen]

Variscite - 4-6-2013 at 12:06

In a water pump for a condenser/distillation setup, what would be the ideal rate of flow (in GPH) for the pump to have?

chemcam - 4-6-2013 at 12:57

Quote: Originally posted by Variscite

In a water pump for a condenser/distillation setup, what would be the ideal rate of flow (in GPH) for the pump to have?

I don't think it really matters what the GPH is as long as there is a constant flow and the reservoir is big enough to allow for a constant temperature throughout the distillation.
I use a salvaged desktop fountain pump, it is very small, but adequate for normal distillations. However, when I setup for refluxing I have to run two pumps together to get constant vertical flow, or elevate the reservoir.

Dr.Bob - 5-6-2013 at 11:28

Quote: Originally posted by confused

Hi, is there any way to make or extract sodium dodecyl sulfate from commonly avalible products
without oleum, chlrosulfuric acid or SO3?

I need some for preparation of some buffer solutions for microbiology

Many shampoos and detergents are nearly pure sodium dodecyl sulfate solutions already. If you find a shampoo without dyes or frangrance, it might be good enough for simple biology work. Just look at the labels.

Boron Trioxide - 5-6-2013 at 20:12

Quick question about HCl

I recently purchased some toilet cleaner stating to be 10% HCl, it sounded like a liquid in the bottle though after checking it is more of a disgusting gel, is there anyway to extract the HCl, perhaps thermal decomposition and re-absorption in water?

Thanks for any answers.

manimal - 6-6-2013 at 18:39

When chlorinating an amino alcohol (tertiary amine, secondary alcohol) with ZnCl2 and HCl, would complexes ruin the party?

Tdep - 7-6-2013 at 05:38

Does plastic destroy chlorine dioxide, ie can I use a plastic testtube when making the gas or do I have to stick with glass (worried about explosions + shrapnel)

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