Sciencemadness Discussion Board - The Short Questions Thread (4)

The Short Questions Thread (4)

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IrC - 4-3-2014 at 02:20

Posting this here as I honestly have no idea where it should go, and it is a question. Namely, what can anyone tell me about this actual patent application (meaning yes it exists), does anyone think it has validity. Found it browsing patents related to electromagnetic heating of the ionosphere.

Infinite speed space communications using information globes

http://www.freepatentsonline.com/y2002/0013139.html

Attachment: US20020013139A1.pdf (324kB)
This file has been downloaded 458 times

This is the most oddly written patent I have ever seen. Referencing books on the history of Tesla among other deviations from what I am used to. Seems he is basing principles upon what I can only view as the type of quantum correlation one thinks of when trying to understand the subject of Bells Inequality, among other principles one would consider when studying the more esoteric subjects in physics. I have not found anything even remotely similar being accepted and listed in search indices at the USPTO before.

[Edited on 3-4-2014 by IrC]

Chemical Engineering Assumptions

Panache - 7-3-2014 at 16:04

Question Prologue
I have long gone by the assumption that vessels and associated piping etc designed to withstand pressure of any reasonable degree (~100psi-ish) can withstand full vacuum (well like 75torr).
This assumption generally holds also for o-ring seals and flanged seals, but I tend to decide upon it on a seal by seal basis (some seals to perform require fish).

Actual Question
Is this assumption generally safe and valid?

(The reason I ask is I was curious as to what would happen if I place a full bottle of liquid CO2 into my ultra-low freezer at -85. Liquid CO2 has a density half that of the solid and I was concerned regarding the integrity of the cylinder. I have since decided there was no real reason for doing it but it made me realise I have never questioned this assumption)

Metacelsus - 7-3-2014 at 17:58

Atmospheric pressure is ~14 psi. I think your assumption is valid.

HeYBrO - 8-3-2014 at 02:16

Edit: Posted in wrong thread. Admin delete post please
[Edited on 8-3-2014 by HeYBrO]

[Edited on 8-3-2014 by HeYBrO]

[Edited on 8-3-2014 by HeYBrO]

DubaiAmateurRocketry - 8-3-2014 at 12:11

How do I calculate the acidity/basicity, or if a compound can be protonated or not?

Metacelsus - 8-3-2014 at 13:34

MOPAC will give pKa values.

bismuthate - 8-3-2014 at 17:36

How could Cr2O3 be oxidized to CrO3?
P.S. Somehow it ssems to me that this would be easy to find but I found nothing. Is this possible? Sorry if it's a stupid question.

learningChem - 13-3-2014 at 11:04

iron + copper sulfate ---> copper + iron sulfate.

Should

aluminium + iron sulfate ---> iron + aluminium sulfate

work? I tried the reaction but apparently it doesn't work. Is it because aluminium and iron are too close in the series?

MrHomeScientist - 13-3-2014 at 12:11

Based on the electrochemical series that should work. Aluminum forms a protective oxide layer that may prevent reaction, though. Copper chloride seems good at getting through this, but to avoid contamination of your iron I'd advise a quick dip in dilute hydrochloric acid until bubbles just start to form, then immediately immerse in your iron solution.

learningChem - 13-3-2014 at 14:48

Thanks MHS. I tried the HCl trick but it doesn't seem to help... - Puzzled.

[Edited on 13-3-2014 by learningChem]

Metacelsus - 19-3-2014 at 13:10

When an iodide salt reacts with concentrated sulfuric acid, is the acid reduced to sulfur dioxide, elemental sulfur, or hydrogen sulfide?

HgDinis25 - 19-3-2014 at 13:15

Quote: Originally posted by Cheddite Cheese

When an iodide salt reacts with concentrated sulfuric acid, is the acid reduced to sulfur dioxide, elemental sulfur, or hydrogen sulfide?

Becaude iodide ion is a strong reducing agent, it can reduce the sulfate ion (SO4) into SO2, then to H2S and even elemental sulfur. So, to answer your question you get a mix of reactions happening at the same time. Because of iodide's reducing power, you'll get mostly H2S and some SO2. It would take even more reducing power to go all the way to elemental sulfur, but tiny quantities may be formed.

DraconicAcid - 19-3-2014 at 13:21

Quote: Originally posted by bismuthate

How could Cr2O3 be oxidized to CrO3?
P.S. Somehow it ssems to me that this would be easy to find but I found nothing. Is this possible? Sorry if it's a stupid question.

Not directly, but chromium(III) salts can be oxidized to chromate in basic solution with peroxide. Chromate can probably be converted to CrO₃ with sufficient conc. sulphuric acid.

Molten Li vs. glass

Zyklon-A - 19-3-2014 at 14:10

Months ago, my torch broke. Yesterday I finally got a new one, and since then I have been busy ampuleing most of my element collection. I tried putting the lithium in an ampule inside a desiccator bag, but it was much too difficult. So I just took it out of my vial, ripped it into little chunks and put it in the ampule. Sealing the ampule was a breeze, and it is sealed in dry CO₂.
I know Li reacts with glass when molten, but how fast? It is covered with the black LiN₃ and looks nothing like a metal. Would it be safe to melt it just a little, and then cool it down quickly? Or would it dissolve the glass to fast? Or would it explode? 2 LiN₃ → 2 Li + 3N₂.

Thanks.
[edit] just realized, Li doesn't react to form LiN₃, but rather Li₃N. Which isn't an azide, and doesn't explode.

[Edited on 19-3-2014 by Zyklonb]

bismuthate - 19-3-2014 at 15:16

Here's a (possibley usefull) video.
http://www.youtube.com/watch?v=cFGejaYqM-c

Zyklon-A - 19-3-2014 at 15:33

Damn, that's more violent than I thought.... But with powdered glass and powdered lithium the surface area increase certainly makes a big difference. Doesn't quite answer my question though, but thanks.

S.C. Wack - 19-3-2014 at 16:09

from
http://www.sciencemadness.org/talk/viewthread.php?tid=20125&...
"On numerous occasions, several of these extruded pieces were melted together in mineral oil, then pipetted into glass tubing to give pieces weighing several grams. In some cases the glass tubes were sealed off and in others the pieces of metal were removed into containers filled with oil (Figure 4). Both types of containers have kept the lithium shiny for over two years."

Zyklon-A - 19-3-2014 at 16:31

Thanks for the idea, I'll do that next time. The ampule is already sealed, and I'd rather not brake it, thus allowing it to be oxidized even more by nitrogen. I do have more Li (still in some batteries,) which I will store in accordance to the method you mentioned.

Should I get this scale?

Zyklon-A - 21-3-2014 at 11:54

http://www.amazon.com/Smart-Weigh-JDS20-Digital-0-001g/dp/B0...
I seems like a great deal. It weighs from 0.001 - 20 grams. Only $18.00 with free shipping on orders over $35.00.

elementcollector1 - 21-3-2014 at 12:16

If you only need to weigh small quantities, go for it. I got a 2000g x 0.1g scale.

Zyklon-A - 21-3-2014 at 12:35

Ok, I already have a 500 x 0.1 gram scale, so this is fine.

HeYBrO - 22-3-2014 at 18:06

Sorry about double post...
Regarding the p-TsOH synth:
(its really noobish, my apologies) if i were to scale down this procedure by 10 times, obviously the water coming off is going to be much less, so how much of my 10 ml dean stark should i fill with toluene. I know that the toluene must be in excess and the amount of water will be probably under a ml ( according to the vocal fifth edition procedure ) I presume about 9 ml toluene in the dean stark from the begging would work to drip over and begin water collection? Or do i have it wrong? ( i should of originally posted this question here... sorry.)

Screen Shot 2014-03-15 at 12.09.52 pm.png - 159kB

[Edited on 23-3-2014 by HeYBrO]

Refinery - 25-3-2014 at 04:55

What is the solubility of potassium sulfate in methanol?
What is the solubility of ammonium nitrate in methanol?

[Edited on 25-3-2014 by Refinery]

copperastic - 25-3-2014 at 17:06

Hi, im looking for a water pump for distillation and i can only find pumps that are 70 GPH. How many GPH's do i need for a condenser?
Thanks.

elementcollector1 - 25-3-2014 at 17:17

Hell, my hose works for a condenser and its output must be somewhere around 10 GPH.

copperastic - 25-3-2014 at 17:27

Where can i get a 10 GPH pump. Ive spent like an hour trying to find one. Thanks.

P.S. My hose is to big to attach.

[Edited on 26-3-2014 by copperastic]

elementcollector1 - 25-3-2014 at 17:32

Does your hose have a thread connector? If so, pop on down to the hardware store and get a brass nipple for the rubber tubing with an appropriate connection to the female end of a hose connector. Cost ~$7, works beautifully.

copperastic - 25-3-2014 at 17:34

ok elementcollector thanks.

Zyklon-A - 25-3-2014 at 18:35

Quote: Originally posted by Refinery

What is the solubility of potassium sulfate in methanol?
What is the solubility of ammonium nitrate in methanol?

No idea why I humored you spoon-feeding request....
Could you not type in Google: solubility of potassium sulfate in methanol?
Anyway, this is pretty good.
This isn't as good.

Brain&Force - 27-3-2014 at 15:21

This isn't really a chemistry question...

I have a Nd:YVO₄ green laser pointer. Neodymium normally emits in the IR range, but a frequency doubler (potassium titanyl phosphate) is used to convert it to green light. If I look through the frequency doubler crystal, will I be able to see the world in infrared? Is there any way to do this with frequency doubling?

GoldGuy - 30-3-2014 at 03:14

Sorry Brain & Force I don't have an answer for you. Anyway...

There is so much ambiguity the solubility of methylamine.
Ive tried to search this one simple question for months
It says right here that methylamine is insoluble in acetone and ethyl acetate? Is this true?
Does anyone know if methylamine is soluble acetone? Are the di and tri methylamines soluble in acetone?

P.S. a bit below it also says MeNH2.HCl is insoluble in most organic solvents. Is this true?

Sea Salt

Zyklon-A - 4-4-2014 at 06:45

I have lots of sea salt in my house, we usually use it instead of pure NaCl to flavor our food.
My question is, is sea salt really evaporated salt water, or do they do anything to remove some of the other salts?
Sea water contains decent amounts of Br^- ions.
and by bubbling chlorine through sea water elemental bromine is isolated industrially. I don't live near an ocean, but making a saturated solution of sea salt, and bubbling chlorine, I could make some bromine if it really is evaporated salt water.
2 Br^- + Cl₂ → Br₂ + 2 Cl^-.
[EDIT] I guess the only way to test is to just try it. Luckily that will be quite easy. Has anyone else tried this? I suppose iodine could be made the same way, and it will be produced first, as it can be reduced by chlorine and bromine.... Separation should be easy.

[Edited on 4-4-2014 by Zyklonb]

forgottenpassword - 4-4-2014 at 07:42

I think that it would be a lot simpler and easier to buy a bromide salt, or pool brominating tablets? What concentration of bromide do you expect from sea salt? I read 0.2%!

[Edited on 4-4-2014 by forgottenpassword]

Zyklon-A - 4-4-2014 at 07:45

I already bought 100 grams of KBr, but it wasn't very cheap.... Yeah it's definitely easier, but this is how it's done industrially, and I want to make larger quantity's of bromine.

forgottenpassword - 4-4-2014 at 08:04

Sodium bromide is cheap in bulk. 25 kg for 120 pounds: http://www.ebay.co.uk/sch/i.html?_trksid=p2050601.m570.l1313...
Perhaps you have bought photographic grade? By all means give it a try with sea salt, but I gather that it is only economical if you have a whole ocean of sea water as your starting material.

Good luck anyway.

Mailinmypocket - 4-4-2014 at 08:11

Search on YouTube for a video by ChemStudy on bromine. It's a very old video but it has a part where they demonstrate lab scale bromine production from sea water, yields are poor but the video is fantastic, as with all the chemstudy episodes!

Zyklon-A - 4-4-2014 at 08:13

Oh, thanks for the link, I don't have 120 pounds ($199.07) but maybe soon. I think what I bought was for spa's but I'd have to check again.
If I do indeed try on a larger scale I will certainly just buy NaBr or KBr bulk, rather than sea salt...
I still would like to try and see if sea salt does contain bromides.
[EDIT]

Quote: Originally posted by Mailinmypocket

Search on YouTube for a video by ChemStudy on bromine. It's a very old video but it has a part where they demonstrate lab scale bromine production from sea water, yields are poor but the video is fantastic, as with all the chemstudy episodes!

I will thanks. I think I did watch it a long time ago, but I must have forgotten.
As you can see I didn't do as much research as I should have.

[Edited on 4-4-2014 by Zyklonb]

Question

azg - 5-4-2014 at 06:37

How to make elemental phosphorous from phosphides?
I have read that they are sold as rodenticides to mix with rat food. I'm an amateur so is there any way I can get phosphorous from metal phosphides like calcium and aluminium phosphide? Because I cannot find elemental phosphorous anywhere. The red one along the side of matchboxes is present in so small quantities

[Edited on 5-4-2014 by azg]

Bert - 5-4-2014 at 07:09

Quote: Originally posted by azg

is there any way I can get phosphorous from metal phosphides like calcium and aluminium phosphide? Because I cannot find elemental phosphorous anywhere. The red one along the side of matchboxes is present in so small quantities

There are several threads devoted to isolating elemental Phosphorus on here, a quick search will get you there.

BTW, those pest control phosphides are FUMIGANTS that release poisonous phosphine gasses. MUCH more dangerous to handle than the phosphates-

So, what is your phosphorous project in relation to?

I hope your next questions aren't about elemental Iodine and/or Lithium metal? Or maybe production of methylamine?

Zyklon-A - 5-4-2014 at 07:12

Red phosphorus is very hard to buy as it is used extensively in the production of methamphetamine.
isolating it is no easier, but not impossible, don't expect to make it in any less than a week, and it may cost a lot of start-up money....
This is a great place to learn some of the common procedure's.
Also...

Attachment: Phosphorus-Microwave.pdf (67kB)
This file has been downloaded 446 times

Attachment: Phosphrous Summation.htm (111kB)
This file has been downloaded 1149 times

copperastic - 6-4-2014 at 04:28

Hello, I was watching a you-tube video that said that hydrochloric acid would react with copper sulfate to form copper chloride, Sulfuric acid, and water. Is this true?

https://www.youtube.com/watch?v=sroXTxFHbec

Galinstan - 6-4-2014 at 06:01

all you will get is all the ions present in a solution and if the Cl- ion is in high enough concnetration the [CuCl4]- complex ion so while there will be copper ion sand chloride ions present in solution they don't go around as CuCl2 in solution and the same for sulphuric acid you will have hydronium ions and bisulphate and sulphate all as a mess in a solution. not sulphuric acid and copper chloride.

Brain&Force - 6-4-2014 at 12:01

If you want to make copper chloride, precipitate the copper sulfate with sodium carbonate/bicarbonate (watch bubbling if you use the bicarbonate) and dissolve the carbonate in hydrochloric acid. Works like a charm and can be used as an etching solution with excess HCl and a bit of hydrogen peroxide.

Question

Zyklon-A - 7-4-2014 at 12:04

Not a chemistry question...
I just received a big MMO plated Ti anode. It's strong as hell, and I've already broken a heavy-duty pair of wire clippers trying to cut it to a smaller size.
Although I haven't tried, it seems like a hacksaw would be hard to use to cut a mesh. It's 10 in by 6 in - way to big for my project, and definitely needs to be shortened. How would I go about cutting it?

copperastic - 7-4-2014 at 12:08

zklonb if you have lots of time you could spend probably a year with a file.

Bert - 7-4-2014 at 12:44

An abrasive cut off wheel at high RPM. Wear protective equipment and a dust mask.

plante1999 - 7-4-2014 at 13:10

I used metal sheet scissors, works very well if you are strong enough.

Zyklon-A - 7-4-2014 at 13:54

Yeah, thanks everyone, I tried sheet metal snips didn't even make a dent. Bert's suggestion is probably the most ideal, but I'd rather not spent any more money, or wait for shipping. I didn't think Ti was even that strong... Perhaps I could use a chisel and hammer to break every wire individually.
[EDIT] Never mind, I used a hammer on the metal snips, it worked great.
I can sell pieces of MMO to anybody that wants one. $2-4/ sq inch (Depending on the amount). Contact via U2U or email.
FREE SHIPPING!

[Edited on 8-4-2014 by Zyklonb]

DubaiAmateurRocketry - 7-4-2014 at 14:05

Are there any complex salts of Aluminum with hydrazine or ammonia? I heard Al(NH3)6 exist?

DraconicAcid - 7-4-2014 at 15:53

Quote: Originally posted by DubaiAmateurRocketry

Are there any complex salts of Aluminum with hydrazine or ammonia? I heard Al(NH3)6 exist?

I don't think aluminum forms stable complexes with nitrogen donors, outside of being dissolved in liquid ammonia. Lang's handbook of chemistry doesn't even list an ethylenediamine complex.

Ozone

Zyklon-A - 8-4-2014 at 07:30

Ozone can be produced by electrolysis of dilute sulfuric acid, with a Pt anode. The process is described here as well as many other places. My question is, could MMO be employed as an anode in place of platinum, or would it be chemically degraded by the ozone produced, or the sulfuric acid?

Zyklon-A - 11-4-2014 at 09:13

Does this look like it would be a good power supply unit for chlorate production?
5 volts 30 amps, for only $26.00, the only reason I'm asking is because I can't see anywhere were it says weather it's DC or AC - which will definitely make a huge difference.
Some more options on amps.

[Edited on 11-4-2014 by Zyklonb]

Vigreux column?

numos - 11-4-2014 at 20:28

Everywhere I look it seems as vigreux columns are looked down upon. Why? I realize they are difficult to clean, but apart from that? I wish to run my first esterification tomorrow, specifically methyl benzoate.

For the reflux I have a 300mm liebig condenser and a 480mm vigreux column [all 24/40]. I really want to use the column as it doesn't require a water setup - which is not a problem I have a pump, but if there a functional simpler route why not use it?

So will it be sufficient? Thanks!

Chemosynthesis - 11-4-2014 at 20:45

Quote: Originally posted by numos

Everywhere I look it seems as vigreux columns are looked down upon. Why?

I have been told they are overrated by people who aren't distillation/reflux afficionados, mostly in fractionation, from what I have seen. I'm an ignorant overrater.

Todd columns and packed columns have always been praised when I've asked people who really specialize in this sort of thing. Todd columns allow you to alter the temperature pretty easily and are supposed to give good resolution. If you want to get even fancier, spinning band columns are good for fractionation too, which I have not used.

I am pretty sure you will be suited well with a Vigreux. I like them, but I am not a specialist in that type of thing. It won't let you use Raschig rings for packing, but you might use beads or broken glass with a glass wool or cotton plug to keep the packing from falling into your reaction mix. For your purposes, a normal packed column is good too because it allows you to tailor the theoretical plate number for separations very easily.

Fill your column up and you rest fairly easy about not losing volatile solvent or product to the atmosphere, but you will have some stuck on your packing material. This can be good, by shifting reaction equilibria due to sequestration, or annoying due to the need to extract said material from your packing.

The Volatile Chemist - 18-4-2014 at 11:44

Quick question, where is the post on size limitations and maximum resolutions of images? I don't care what the maxes are, I just want to see the post.

(Woot! Over 100 posts!)

[Edited on 4-18-2014 by The Volatile Chemist]

DubaiAmateurRocketry - 19-4-2014 at 01:37

What shall we do before we touch things like cyanide, hydrazine, azides? Cyanide and azide stops cecullar respiration which is fatal, is there any antidote or things you can do if you're poisoned? I am obviously not touching any cyanides, just asking out of curiosity. I heard vitamine B12 could get rid of cyanide and azide anion? However if lets say I ate twice more than the LD50 for a cyanide poison, however I took equivalents of vitamine B12 tablets prior to the ingestion, will I still die?

Question

Zyklon-A - 19-4-2014 at 14:22

When distilling nitric acid, would it not be more practical to use a water bath as a heat source? The boiling point of nitric acid is 83°C, so even below water's BP should work fine. I ask because I've never seen or heard of people using water - an oil bath or just raising it above the hotplate is what I have seen.

DubaiAmateurRocketry - 19-4-2014 at 14:42

Quote: Originally posted by Zyklonb

When distilling nitric acid, would it not be more practical to use a water bath as a heat source? The boiling point of nitric acid is 83°C, so even below water's BP should work fine. I ask because I've never seen or heard of people using water - an oil bath or just raising it above the hotplate is what I have seen.

Depends what type of distillation you're doing. If you're trying to concentrate nitric acid from a dilute solution (reason for most of us to do distillation on nitric acid) I am sorry to tell you that nitric acid does not boil in a water solution up to 121 degree celsius. You can try an oil bath.

bismuthate - 19-4-2014 at 14:57

Well I would guess that the contaminants would raise the boiling point of the HNO3 to a point when using water would be pointless or inefective. This is, however, merely an educated guess.
Oops I posted to late

[Edited on 19-4-2014 by bismuthate]

Zyklon-A - 19-4-2014 at 15:07

Ok, I was just checking. I will be preparing it, from 98% sulfuric acid and a nitrate salt.

Chemosynthesis - 21-4-2014 at 06:15

Quote: Originally posted by DubaiAmateurRocketry

What shall we do before we touch things like cyanide, hydrazine, azides? Cyanide and azide stops cecullar respiration which is fatal, is there any antidote or things you can do if you're poisoned? I am obviously not touching any cyanides, just asking out of curiosity. I heard vitamine B12 could get rid of cyanide and azide anion? However if lets say I ate twice more than the LD50 for a cyanide poison, however I took equivalents of vitamine B12 tablets prior to the ingestion, will I still die?

Cyanide antidote kits consist of inhalational amyl nitrite, a "popper," IV sodium nitrite/thiosulfate, or hydroxocobalamin. Not sure off the top of my head how therapeutic B<sub>12</sub> would be given the last one. I've only seen the old kits lying around so far.
Azides have no real prophylaxis or prognostic treatment last I checked, and I work with them daily. PMID: 17724902 suggests that cyanide kits may be effective in mitigating azide poisoning, but I'm a little sceptical given what I'd read previously. Either way, Br J Clin Pharmacol. Jan 1998; 45(1): 83–86 (doi: 10.1046/j.1365-2125.1998.00642.x) suggests that insufflation of hydroxocobalamin reaches peak plasma concentration within about 35 minutes, and inhalation/insufflation should be less variable than ingestion. I'm not about to suggest stocking up on IM solutions and insulin syringes, so the pharmacokinetic question then would be what type of cobalamin are you getting at the store, and what is the interconversion to the free plasma hydroxocobalamin?
Best never to work with these types of substances alone and always use adequate protective gear.

[Edited on 21-4-2014 by Chemosynthesis]

Dr.Bob - 21-4-2014 at 10:39

Quote: Originally posted by numos

For the reflux I have a 300mm liebig condenser and a 480mm vigreux column [all 24/40]. I really want to use the column as it doesn't require a water setup - which is not a problem I have a pump, but if there a functional simpler route why not use it?

So will it be sufficient? Thanks!

I often put first a Vigreux column and then on top of that an extra liebig (no water attached) as a simple reflux condenser. Then you simply moderate the heat such that the liquid condenses on the bottom of the Vigreux. Remember, once the liquid is boiling, you can often turn the heat down a bit until it is just barely boiling, such that you don't need much cooling ability to keep the solvent condensing.

There is no temperature advantage to vigorously boiling the reaction verses simply letting it barely boil-both will be the same temp, the BP. Any boiling will require the same amount of heat to be extracted from the condenser as applied by the heat source to boil the solvent, but keeping the temp just at the BP can be done with only enough heat to replace that lost to the surroundings.

Iron - Iron oxalate

learningChem - 22-4-2014 at 20:36

Is it possible to decompose iron oxlate to get iron that is NOT pyrophoric? Is there a way to control the particle size?

learningChem - 22-4-2014 at 20:37

oops - I meant to post this in the short questions thread - feel free to delete the post.

Zephyr - 27-4-2014 at 15:43

I got found this from a friend who thought it came from an old lab, does anyone know what it is?
My best guess is that its a TLC plate, but I can not find any like it. If it is a TLC plate, would I prepare it by spreading the media in the indent? Like how microscope slide TLC plates are made?
you can't see it in the picture, but it says KONTES 1000µ. This obviously the brand, and the groove is 1000µ deep?

DraconicAcid - 27-4-2014 at 16:54

It might be a gel electrophoresis plate. I'd assume your guess about the depth is correct.

Brain&Force - 29-4-2014 at 12:54

What are the best coloring agents for methanol? I've tried the "thunder flask" demo where methanol is added to a narrow-necked flask and ignited. However, I haven't found any good coloring agents other than boric acid. Are there any other good and easily available ones? I've tried copper chloride and strontium nitrate, but they don't disperse and therefore leave the flame only partially colored.

Zyklon-A - 30-4-2014 at 12:10

How high a concentration of nitric acid in water can be achieved by dissolving NO₂ + O₂ in H₂O at 2 ATM at 10°C?
[4 NO₂ (g) + O₂ (g) + 2 H₂O (l) → 4 HNO₃ (aq)]

Brain&Force - 30-4-2014 at 15:40

May be a better idea to use hydrogen peroxide, if available. It provides a higher yield. Even 3% is better than nothing. The reaction is a disproportionation and nitrous acid is formed as well when just water is added.

Zyklon-A - 1-5-2014 at 06:16

I'm asking about how it could be done large scale, I have H₂O₂, but I don't want to use it. Excess oxygen is much cheaper, under pressure gasses dissolve better, so a decent concentration could be made, I just don't know what.

[Edited on 1-5-2014 by Zyklonb]

Bert - 1-5-2014 at 07:14

Quote: Originally posted by Brain&Force

What are the best coloring agents for methanol? I've tried the "thunder flask" demo where methanol is added to a narrow-necked flask and ignited. However, I haven't found any good coloring agents other than boric acid. Are there any other good and easily available ones? I've tried copper chloride and strontium nitrate, but they don't disperse and therefore leave the flame only partially colored.

We do colored methanol fireballs as part of pyrotechnic special effects work- But OUTDOORS! Sometimes with many liters of methanol, which produces some formaldehyde in open burning (or in your liver if you inhale the fumes), and organic chlorine donors to improve blue flame color- Which produces a little PHOSGENE in open burning. Not a classroom demo, outside of a good fume hood.

If you want a colored alcohol flame, you will need a metal salt that dissolves in the methanol. About 13 grams per liter of any of the chemicals below is plenty-

Don't bother with the usual Strontium for red and Barium for green. You would need the chlorine donors, better to use Boron, Lithium and Potassium.

Boric acid dissolves and creates methyl borate, gives a good green but somewhat toxic (not that breathing Barium would be any better!).

Try Potassium iodide for a nice purple color. Dissolves in methanol well, I like it better than Strontium colors.

Calcium chloride gives orange.

Sodium chloride for yellow. And it will contaminate any of the others and turn them yellow too (even a slight amount of contamination is too much), so handle it LAST. Sodium is an incredibly strong emitter in that narrow orangey yellow range- Destroys colors in solid pyrotechnic color compositions in small amounts too.

Copper chloride + an organic chloride or fluoride (methylene chloride is one choice) gives a blue- along with phosgene. You CAN substitute hydrochloride acid, but then you have acid mist. Blue is pretty, pretty dangerous that is.

Look here, on page 14.

http://www.youtube.com/watch?v=eRNLqTfIjQo&sns

Brain&Force - 1-5-2014 at 17:13

I've tried strontium nitrate in methanol, but it doesn't dissolve volatilize and give an even color to the flame, unlike, for example, alkylborates. I didn't think of chlorine donors, though - this may be a good idea.

I tried strontium nitrate, but it didn't dissolve in the methanol at all, and it had a mix of red, blue, and gray in the flame. (I think the gray is a methyl nitrite or methyl nitrate ester.)

Anyone know any strontium/lithium or any other red-burning salt that is soluble in methanol?

[Edited on 2.5.2014 by Brain&Force]

alexleyenda - 1-5-2014 at 17:36

Quote: Originally posted by Pinkhippo11

I got found this from a friend who thought it came from an old lab, does anyone know what it is?
My best guess is that its a TLC plate, but I can not find any like it. If it is a TLC plate, would I prepare it by spreading the media in the indent? Like how microscope slide TLC plates are made?
you can't see it in the picture, but it says KONTES 1000µ. This obviously the brand, and the groove is 1000µ deep?

The fact that they give you the dept with such precision makes me believe it is actually used for physics experiments with light, maybe on refraction or on light interference. In optical physic, you work a lot with glass instruments with depths and slots in micrometers and wavelengths in nanometers, so it would make sense to give such a precise depth while it doesn't really matter in TLC or electrophoresis at my knowledge. Why would they bother give the depth number with 4 significative digits instead of just writing "1 mm" if it didn't matter :p If you find what it's used for let us know

[Edited on 2-5-2014 by alexleyenda]

DubaiAmateurRocketry - 4-5-2014 at 02:31

Quote: Originally posted by DraconicAcid

Quote: Originally posted by DubaiAmateurRocketry

Are there any complex salts of Aluminum with hydrazine or ammonia? I heard Al(NH3)6 exist?

I don't think aluminum forms stable complexes with nitrogen donors, outside of being dissolved in liquid ammonia. Lang's handbook of chemistry doesn't even list an ethylenediamine complex.

https://docs.google.com/viewer?url=patentimages.storage.goog...

I found this patent describing Al(N2H4)6(ClO4)3.

I am not sure if the nitrate or dinitramide salt exist, these would be interesting in energetics.

Barbier Reaction

Metacelsus - 4-5-2014 at 18:25

I know the Barbier reaction is usually used for allylation. Can it also work for benzylation?

[Edited on 5-5-2014 by Cheddite Cheese]

Etaoin Shrdlu - 4-5-2014 at 19:26

Quote: Originally posted by Cheddite Cheese

I know the Barbier reaction is usually used for allylation. Can it also work for benzylation?

[Edited on 5-5-2014 by Cheddite Cheese]

Apparently. http://www.arkat-usa.org/get-file/34424/

Töilet Plünger - 5-5-2014 at 13:14

Quote: Originally posted by Brain&Force

Anyone know any strontium/lithium or any other red-burning salt that is soluble in methanol?

I'll answer my own question: lithium nitrate. Though I'm not sure if it'll burn nicely; I haven't tried it yet.

[edit] it does!

[Edited on 2014-5-6 by Töilet Plünger]

elementcollector1 - 7-5-2014 at 21:43

Solubility Data: (NH₄)₂SO₄ in HNO₃ / H₂SO₄?
Exactly what it says - is ammonium sulfate soluble to any appreciable degree in either of these acids, at low temperatures (assume 0 to 20 degrees C)?

Oscilllator - 8-5-2014 at 04:15

I imagine they would be soluble to a limited degree. Nitrating baths can be made of NH4NO3 and H2SO4, and the NH4NO3 dissolves into the sulfuric acid to an appreciable extent to create nitric acid. This is a very similar situation.
I don't know the precisely how soluble they would be, but I imagine you should be able to get a 5-10% soln fairly easily

Soxhlet extractor question

Hegi - 8-5-2014 at 08:32

I´m buying soxlet extractor with volume of 150 ml and I was looking for extraction thimbles.. They are not cheap at all and what I found is package of 25 pieces with size 34mm in external diameter and lenght 100mm for 35 pounds with shipping.. my question is if it would fit in and work ? Does anyone know? Or shall I rather look for 22x80 thimbles?

Etaoin Shrdlu - 8-5-2014 at 10:00

Give the supplier your dimensions and ask them.

Zyklon-A - 8-5-2014 at 10:21

Quote: Originally posted by elementcollector1

Solubility Data: (NH₄)₂SO₄ in HNO₃ / H₂SO₄?
Exactly what it says - is ammonium sulfate soluble to any appreciable degree in either of these acids, at low temperatures (assume 0 to 20 degrees C)?

http://www.uea.ac.uk/~e770/aim/model2/descr2.htm

solo - 9-5-2014 at 05:39

.......when halogenating an aldehyde with the alpha carbon without any free hydrogens, if there is al alkene adjacent to the alpha carbon will the halogenation favor the aldehyde or the alkene or both.....solo

Note- March 5th edition page 914 sectsion 14-3, talks about the halogenation of aldehydes with the alpha carbon abscent of any hydrogens

[Edited on 9-5-2014 by solo]

Metacelsus - 9-5-2014 at 11:12

If there are no alpha hydrogens, halogenation will not occur (what atom would the halogen replace?). I think the halogen would just add across the double bond.

solo - 9-5-2014 at 12:39

.......the hydrogen on the aldehyde...as stated on the reference provided......will get halogenated, but my question is will the alkene be halogenate as well or just the aldehyde site.....solo

[Edited on 9-5-2014 by solo]

Metacelsus - 9-5-2014 at 15:02

So the reaction forms an acyl halide? Very interesting . . .

solo - 9-5-2014 at 15:22

.....well, if it halogenates an aldehyde with no alpha hydrogen it would be great...if only the alkene attached to the alpha carbon is not halogenated with this particular type of aldehyde.....one can do many things with that .....hence the reason for my inquiry....solo

[Edited on 10-5-2014 by solo]

Metacelsus - 10-5-2014 at 13:53

Quote: Originally posted by solo

Note- March 5th edition page 914 section 14-3

edition of what?

Also, what would prevent the alkene from being halogenated?

Can you be more specific about conditions, substrate, etc.?

Brain&Force - 13-5-2014 at 19:33

I mixed potassium nitrate in methanol. It doesn't appear to dissolve, but the methanol turns blue. I've also had this happen with a sample of methanol sitting in a low-oxygen environment with just a match in it (there weren't any nitrates in the methanol). What causes this?

Zephyr - 13-5-2014 at 20:27

I have recently made what I believe to be copper nitrite, by the addition of copper sulfate to a small excess sodium nitrite. The solution is dark green, similar to concentrated copper chloride. I wish to isolate the copper nitrite, but am unsure about how to go about it. Does anyone have any information on copper nitrite? Or any ideas on how to separate it?

Etaoin Shrdlu - 13-5-2014 at 20:48

You just have a mixture of copper, sodium, sulfate, and nitrite ions now.

Zephyr - 13-5-2014 at 20:56

Yes I know. However this doesn't answer any of my questions. I have looked in the Merck index and in the CRC, and neither contain anything on copper nitrite.

Etaoin Shrdlu - 14-5-2014 at 10:12

Sorry, let me try again. You haven't "made" copper nitrite because none of the compounds changed states, you have made a mixture of copper, sodium, sulfate, and nitrite ions.

I'm almost 100% certain you can't isolate copper nitrite without it decomposing. Maybe with highly specialized equipment and conditions. Sodium sulfate looks marginally less soluble than copper sulfate or sodium nitrite at cool temperatures, perhaps it is possible to crystallize that out...

[Edited on 5-14-2014 by Etaoin Shrdlu]

bismuthate - 15-5-2014 at 13:05

So earlier today a mixed solutions of povidone iodine that was neutralized with excess sodium thiosulfate. This instantly precipitated an orangish yellow precipitate. What happened here?
EDIT: it starts out yellow and turns orange quickly.

[Edited on 15-5-2014 by bismuthate]

Metacelsus - 15-5-2014 at 15:29

The reaction should produce tetrathionate. Could this possibly be decomposing to sulfur?

bismuthate - 15-5-2014 at 15:33

The yellow is much brighter that sulfur.My theory is that the tetrathionate decomposes to the sulfide.

Brain&Force - 18-5-2014 at 11:35

More flame questions:

First of all, is it possible to color the flame of a fireplace or some other wood fire (in other words, a vapor-diffusion flame)? I've tried just dumping copper sulfate on wood fires, but with very little change.

Second, when it is said that the bluest part of a flame is the hottest, isn't that technically inaccurate? Isn't the bluest part the best-mixed part of the flame, where there is enough oxygen to burn completely? And isn't the color caused by the emission spectrum of the burning substance?

DraconicAcid - 18-5-2014 at 12:15

Quote: Originally posted by Brain&Force

More flame questions:

First of all, is it possible to color the flame of a fireplace or some other wood fire (in other words, a vapor-diffusion flame)? I've tried just dumping copper sulfate on wood fires, but with very little change.

Copper perchlorate works wonderfully well for this.

alexleyenda - 18-5-2014 at 17:53

Quote: Originally posted by Brain&Force

Second, when it is said that the bluest part of a flame is the hottest, isn't that technically inaccurate? Isn't the bluest part the best-mixed part of the flame, where there is enough oxygen to burn completely? And isn't the color caused by the emission spectrum of the burning substance?

How wonderful, I am studying that right now in physics. Every particle that moves (has heat) emits electromagnetic radiations (visible light, infrared, etc.). Particles around our temperature (20°C) emits infrared light. When it gets hotter, the energy emited is stronger, the frequency gets higher and the wavelenght lower : we start to get to the visible spectrum, things are red (like heating ovens). When it gets a bit hotter, it continues to go up the spectrum, it gets yellow. Once it gets hotter than that, it is around the middle of the visible spectrum, it emits a good quantity of light of all the wavelengths of the spectrum : all colors together = white. When the energy is higher, the light emited is at the top of the visible spectrum (blue) and UV. That's why UV protection is used by those who bind metal together ( I don't know the word for it in english). Finaly, when it is hotter than that, it is 100% UV or even stronger. The equation to know the principal wavelength emited is "0,0029/T " where T is the temperature in Kelvins. For exemple, the wire in a light bulb is around 3000K, its principal wavelenght is 967 nanometers, which is infrared. It also emits light near that number. 700 being red, that's why light bulbs with wires are red/yellow. It also means that most of its power is lost in infrared that we cannot see, that's why these bulbs efficiency is so bad. The spectrums look like this : (http://faculty.virginia.edu/consciousness/images/black%20bod...)

That being said, light is also created not only by heat, but also when an electron absorbs energy, get to an higher level of energy, then release the energy absorbed as a photon (light) to get back to normal. Depending of the electronic configuration of the atoms, it can only acces to precise levels of energy, so it will always let go only precise amounts of energy corresponding to these levels. That is why compounds let go different colours. The addition of the wavelengts they can release makes their color.. (That is how fluo light bulb work, the electrons of a gas that emit wavelengths in the visible spectrum are excited by an electrical current, then release their energy as light. That is why these bulbs are a lot more efficient than the others which release a lot of invisible particules of light). These spectrums looks like this : http://utahscience.oremjr.alpine.k12.ut.us/sciber06/9th/stan...

[Edited on 19-5-2014 by alexleyenda]

alexleyenda - 18-5-2014 at 18:18

I thought about it, I didn't really answer cleary. To answer more directly to your question, the bluest part really is the hottest, except if you put a compound in it with an emission spectrum that releases blue.
Yes, it is usually the best mixed part where it burns completely, because the more it burns, the more energy is released, the hotter it gets, the frequency gets higher and the wavelenght (in that case) gets more blue.
The color may be caused by the emission spectrum of the burning substance, but most of the time, it is not. Most molecules and atoms require extreme excitation to give off visible light, a flame is not enough to triger that, except in the case of some compounds such as copper, lithium and all.

[Edited on 19-5-2014 by alexleyenda]

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