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DraconicAcid
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Quote: Originally posted by Morgan  | | I was wondering what salt has the highest melting point? Just looking up a few I could think of, calcium fluoride was the highest at 1418 C/2584 F. Or
is there a combination of two salts that might work together that have some high melting point? |
Mixtures of salts will have lower melting points.
Do you consider oxides to be salts?
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Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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Morgan
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It was just a passing thought after seeing a clip of NaCl in water which melts at 1474F/801C and wondering what other salts would do.
https://www.youtube.com/watch?v=PDRWQUUUCF0#t=2m
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Metacelsus
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SrF2 melts a bit higher, at 1477 C. Oxides and nitrides have much higher melting points.
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xfusion44
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What would be the product of combining iodine chloride and ethene? Would this reaction require any catalysts or special conditions?
Thanks in advance
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The Volatile Chemist
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| Quote: | | Quote: Originally posted by PHILOU Zrealone | | Quote: Originally posted by The Volatile Chemist | What's the most basic, relatively safe way to make a black-powder-esque pulver from ammonium nitrate without sulfur, and how does one go about making
a bang with it? I just need something small for independence day, to tear apart a small cheese block(speaking literally, sharp cheddar cheese)...
Definitely not a kewl, but one needs some fun once and a while. Thanks for any help. |
NH4NO3/C to make a banger...that will be hard!
Maybe add a little very fine Al powder, but your NH4NO3 needs to be very dry (it is hygroscopic) to get a kind of flash.
Use C black of fume, it is very light and ultrafine for a better homogeneity of the mix.
Then do an ignition test in the open.
Then do a confinement test into a cardboard roll, with a fuse and cardboard stopers...or simpler into the famous triangle banger with a fuse out of a
corner (triangle made from a ribbon of paper).
[Edited on 24-6-2016 by PHILOU Zrealone] |
Thanks! I'll try that. I don't have any Al, but I'll see what I can do. Hopefully ground up prills of AN will do, if I use the stuff quickly. I wasted
a lot of time today trying to get some AN/Sucrose crap to light, wouldn't work. Was terribly humid out though. Is it really that hard to get AN mixed
with a random fuel to at least burn? |
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PHILOU Zrealone
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| Quote: | | Quote: Originally posted by The Volatile Chemist | | Quote: Originally posted by PHILOU Zrealone | | Quote: Originally posted by The Volatile Chemist | What's the most basic, relatively safe way to make a black-powder-esque pulver from ammonium nitrate without sulfur, and how does one go about making
a bang with it? I just need something small for independence day, to tear apart a small cheese block(speaking literally, sharp cheddar cheese)...
Definitely not a kewl, but one needs some fun once and a while. Thanks for any help. |
NH4NO3/C to make a banger...that will be hard!
Maybe add a little very fine Al powder, but your NH4NO3 needs to be very dry (it is hygroscopic) to get a kind of flash.
Use C black of fume, it is very light and ultrafine for a better homogeneity of the mix.
Then do an ignition test in the open.
Then do a confinement test into a cardboard roll, with a fuse and cardboard stopers...or simpler into the famous triangle banger with a fuse out of a
corner (triangle made from a ribbon of paper).
[Edited on 24-6-2016 by PHILOU Zrealone] |
Thanks! I'll try that. I don't have any Al, but I'll see what I can do. Hopefully ground up prills of AN will do, if I use the stuff quickly. I wasted
a lot of time today trying to get some AN/Sucrose crap to light, wouldn't work. Was terribly humid out though. Is it really that hard to get AN mixed
with a random fuel to at least burn? |
Al powder you can do from Al foil set into a ball form and scratched at emeri/sand paper...hard Al tool works also.
Yes AN is very hard to ignite especially with succrose that releases water when heated (polylol thus a lot of HO groups).
Also with AN/fuel the more the inimate the mix, the better it will start to burn and sustain...correct weight ratio is of course needed -->
stoechiometry
[Edited on 27-6-2016 by PHILOU Zrealone] |
PH Z (PHILOU Zrealone)
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PHILOU Zrealone
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| Quote: Originally posted by xfusion44 | What would be the product of combining iodine chloride and ethene? Would this reaction require any catalysts or special conditions?
Thanks in advance |
This is a beginner question for the beginning section...
Unlike conventional halogenation with Cl2 that may sometimes require a catalyst to help making Cl(+) (like for benzene or unactivated alcenes
(electron withdrawing groups rich alcenes)
AlCl3 + Cl2 --> AlCl4(-) + Cl(+)
For ethene normally a simple mix with Cl2 will result in addition.
CH2=CH2 + Cl2 --> Cl-CH2-CH2-Cl
This can happen by homolytic clivage of Cl2 into 2 Cl° or in heterolytic clivage into Cl(-) and Cl(+)...
This goes even better with I-Cl since it is naturally splitting into I(+) and Cl(-)
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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The Volatile Chemist
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| Quote: | | Quote: Originally posted by PHILOU Zrealone | | Quote: Originally posted by The Volatile Chemist | | Quote: Originally posted by PHILOU Zrealone | | Quote: Originally posted by The Volatile Chemist | What's the most basic, relatively safe way to make a black-powder-esque pulver from ammonium nitrate without sulfur, and how does one go about making
a bang with it? I just need something small for independence day, to tear apart a small cheese block(speaking literally, sharp cheddar cheese)...
Definitely not a kewl, but one needs some fun once and a while. Thanks for any help. |
NH4NO3/C to make a banger...that will be hard!
Maybe add a little very fine Al powder, but your NH4NO3 needs to be very dry (it is hygroscopic) to get a kind of flash.
Use C black of fume, it is very light and ultrafine for a better homogeneity of the mix.
Then do an ignition test in the open.
Then do a confinement test into a cardboard roll, with a fuse and cardboard stopers...or simpler into the famous triangle banger with a fuse out of a
corner (triangle made from a ribbon of paper).
[Edited on 24-6-2016 by PHILOU Zrealone] |
Thanks! I'll try that. I don't have any Al, but I'll see what I can do. Hopefully ground up prills of AN will do, if I use the stuff quickly. I wasted
a lot of time today trying to get some AN/Sucrose crap to light, wouldn't work. Was terribly humid out though. Is it really that hard to get AN mixed
with a random fuel to at least burn? |
Al powder you can do from Al foil set into a ball form and scratched at emeri/sand paper...hard Al tool works also.
Yes AN is very hard to ignite especially with succrose that releases water when heated (polylol thus a lot of HO groups).
Also with AN/fuel the more the inimate the mix, the better it will start to burn and sustain...correct weight ratio is of course needed -->
stoechiometry
[Edited on 27-6-2016 by PHILOU Zrealone] |
Sorry, I don't know how the quotes in this got messed up. But I'll try the Al/file idea, I have a heatsink I could use. Thanks again for your
assistance; I always assumed that sucrose would be a good fuel, but I guess since glucose used to be called carbon hydrate, sugars in general make
terrible fuels. So hydroscopic oxidizers and things that burn with lots of water and not much thermal output don't work too well together.
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nezza
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Antimony(III) and (V)
Hi. I have an acid solution containing antimony(III) and (V). Is there some way of reducing antimony(V) to (III) and no further or a way of separating
the two species.
If you're not part of the solution, you're part of the precipitate.
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xfusion44
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| Quote: Originally posted by PHILOU Zrealone | | Quote: Originally posted by xfusion44 | What would be the product of combining iodine chloride and ethene? Would this reaction require any catalysts or special conditions?
Thanks in advance |
This is a beginner question for the beginning section...
Unlike conventional halogenation with Cl2 that may sometimes require a catalyst to help making Cl(+) (like for benzene or unactivated alcenes
(electron withdrawing groups rich alcenes)
AlCl3 + Cl2 --> AlCl4(-) + Cl(+)
For ethene normally a simple mix with Cl2 will result in addition.
CH2=CH2 + Cl2 --> Cl-CH2-CH2-Cl
This can happen by homolytic clivage of Cl2 into 2 Cl° or in heterolytic clivage into Cl(-) and Cl(+)...
This goes even better with I-Cl since it is naturally splitting into I(+) and Cl(-)
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Thanks! So, this would result in 1,1 dichloroethane or 1,2 chloroiodoethane?
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PHILOU Zrealone
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| Quote: Originally posted by xfusion44 | | Quote: Originally posted by PHILOU Zrealone | | Quote: Originally posted by xfusion44 | What would be the product of combining iodine chloride and ethene? Would this reaction require any catalysts or special conditions?
Thanks in advance |
This is a beginner question for the beginning section...
Unlike conventional halogenation with Cl2 that may sometimes require a catalyst to help making Cl(+) (like for benzene or unactivated alcenes
(electron withdrawing groups rich alcenes)
AlCl3 + Cl2 --> AlCl4(-) + Cl(+)
For ethene normally a simple mix with Cl2 will result in addition.
CH2=CH2 + Cl2 --> Cl-CH2-CH2-Cl
This can happen by homolytic clivage of Cl2 into 2 Cl° or in heterolytic clivage into Cl(-) and Cl(+)...
This goes even better with I-Cl since it is naturally splitting into I(+) and Cl(-)
|
Thanks! So, this would result in 1,1 dichloroethane or 1,2 chloroiodoethane? |
Almost correct!
1,2-dichlor(o)ethane and 1,2-chloroiod(o)ethane.
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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DraconicAcid
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1,2-dichloroethane and 1-chloro-2-iodoethane.
Please remember: "Filtrate" is not a verb.
Write up your lab reports the way your instructor wants them, not the way your ex-instructor wants them.
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PHILOU Zrealone
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Yes, thank you for the correction.
That's what happens when you do two things at the same time 
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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Velzee
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I understand that it could be highly dangerous, but how can one produce and collect dioxins from plastic? Or is it too foolish to even attempt such a
thing?
[Edited on 6/29/2016 by Velzee]
Check out the ScienceMadness Wiki: http://www.sciencemadness.org/smwiki/index.php/Main_Page
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—Arthur Schopenhauer
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Metacelsus
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Dioxins are formed when PVC undergoes incomplete combustion. You could probably make enough dioxins this way to cause toxicity, but you'd have very
little hope of separating them from all the other pyrolysis products. I really shouldn't have to say this, but making dioxins is a bad idea. Don't do
it.
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Velzee
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| Quote: Originally posted by Metacelsus | | Dioxins are formed when PVC undergoes incomplete combustion. You could probably make enough dioxins this way to cause toxicity, but you'd have very
little hope of separating them from all the other pyrolysis products. I really shouldn't have to say this, but making dioxins is a bad idea. Don't do
it. |
I don't want anyone thinking I'm plan to poison anyone, so let it be know that I'm researching various chemicals that cause toxicity and death in past
occurrences, for preparation for my future forensic career, and for organic chemistry.
Check out the ScienceMadness Wiki: http://www.sciencemadness.org/smwiki/index.php/Main_Page
"All truth passes through three stages. First, it is ridiculed. Second, it is violently opposed. Third, it is accepted as being self-evident."
—Arthur Schopenhauer
"¡Vivá Cristo Rey!"
—Saint José Sánchez del Río |
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PHILOU Zrealone
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| Quote: Originally posted by Velzee | | Quote: Originally posted by Metacelsus | | Dioxins are formed when PVC undergoes incomplete combustion. You could probably make enough dioxins this way to cause toxicity, but you'd have very
little hope of separating them from all the other pyrolysis products. I really shouldn't have to say this, but making dioxins is a bad idea. Don't do
it. |
I don't want anyone thinking I'm plan to poison anyone, so let it be know that I'm researching various chemicals that cause toxicity and death in past
occurrences, for preparation for my future forensic career, and for organic chemistry. |
You will probably get more succes at synthetizing it from good precursors...
I have thought about it a lot but not for polyhalodioxines, for polynitrodioxines (as potent dense explosive/energetic materials and polymers of those
for propellant applications)...
--> ortho-halo-phenates, orthohalophenol, o-hydroquinone and heating.
The rest of the halogens may be present into the initial molecule (example pentachlorophenol -heat-> octachlorodioxine) or added afterwards by
conventional halogenation techniques although orientation selectivity may be difficult and may require synthetic pathway prevision to introduce
desired groups at specific places (-NO2 or -CO2H to turn into -NH2 by reduction or rearrangement and then replace by -X (X=I,Br or Cl) by diazotation)
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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careysub
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enammonium-iminium rearrangement
As I proceed with my project of learning some organic chemistry terminology (does anyone ever learn more than "some"?) I find myself perplexed about
the term "enammonium".
The term "iminium" is well described, and widely used; but I am unclear about the term "enammonium" which does not appear even once in March, 6th
edition, for example.
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Crowfjord
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I don't think Ive ever come across the term "enammonium," but it is easy enough to assume that it refers to the positively charged version of an
enamine, which would perhaps show up in the mechanism of enamine/imine tautomerism. Is this a term you came across and did not understand, or one
which you think should exist, but have not seen?
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woelen
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An enamine is an organic amine, with the nitrogen atom directly bonded to a carbon atom which has a double bond to another carbon atom. An example of
an enamine is the following:
CH2=CH-NH2
Another example is:
CH2=CH-N(CH3)2 (both hydrogens on the N substituted by methyl)
When an acid is added to an enamine, then an enammonium salt is produced. In my example:
CH2=CH-NH2 + H(+) --> CH2=CH-NH3(+)
----------------------------------
An imine is an organic compound with a C=N-group in it, e.g. H2C=N-H. Another example is H2C=N-CH3.
-----------------------------------
Enamines with a hydrogen atom connected to the nitrogen atom can rearrange into imines. This reaction is reversible in some cases. An example:
CH2=CH-NH2 <---> CH3-CH=NH
The hydrogen atom "wanders" from the nitrogen atom to the C-atom at the other end of the molecule and the double bond flips from C/C to C/N.
This is possible for any imine with an H atom on the N-atom. Another example:
C(CH3)2=CH-NH(CH3) <---> CH(CH3)2-CH=N-CH3
The acid salts of imines are called iminium salts.
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careysub
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| Quote: Originally posted by Crowfjord | | I don't think Ive ever come across the term "enammonium," but it is easy enough to assume that it refers to the positively charged version of an
enamine, which would perhaps show up in the mechanism of enamine/imine tautomerism. Is this a term you came across and did not understand, or one
which you think should exist, but have not seen? |
I came across the rearrangement of my post's title. But to understand what it is, I need to understand both parts of the rearrangement, but I only
could find definitions for "iminium" (which I already understood). "Enammonium" is used (you can Google it), but not often, and is absent from any of
the standard texts on organic chemistry I consulted (like March) and nowhere did I find anyone offering a definition. As a relatively neophyte student
of the subject I am cautious about trying to assume things - it is too easy to assume incorrectly.
Woelen seems to clarify the issue, I will need to study it a bit more to make sure it is clear to me.
[Edited on 29-6-2016 by careysub]
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PHILOU Zrealone
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Like Woelen said!
The equilibrium en(e)amine <--> imine is known and widely explained in organic textbooks ; it is similar to the en(e)ol-keton equilibrium but
with an amine instead of an alcohol group.
R-CH=CH-NH2 <==> R-CH2-CH=NH
R-CH=CH-OH <==> R-CH2-CH=O
"EN(E)" thus refers to the alcene related structure...
Since imine may form an iminium cation when exposed to a proton R-CH2-CH=NH2(+)
maybe they are proposing the "quadrature of the circle" by talking about en(e)aminium (or what should be the same en(e)ammonium) --> R-CH=CH-NH3(+)
A typical "en(e)-aminium" cation is "anilinium" or "benzenaminium" because the carbon holding the -NH2 (or -NH3(+)) (of anilin/aminobenzene) is
alcenic by nature (sp2 conformation involved into the aromatic ring resonance which is against the iminium structure what would imply a rupture of
aromaticity --> minor equilibrium form).
[Edited on 30-6-2016 by PHILOU Zrealone]
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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Volanschemia
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| Quote: Originally posted by gdflp | | I'm not sure how available nitrates are in Aus currently, but one method which I find quite effective to remove organic tars(I've heard it works for
sulfur too, haven't tried it) from condensers and flasks is to simply prepare some nitric acid with the contaminated glassware. The hot nitric acid
oxidizes anything organic(or sulfur hopefully) to either gaseous(CO<sub>2</sub> and H<sub>2</sub> for organics) or liquid
forms. With sulfur you would form either sulfur dioxide or sulfuric acid, neither one is a big deal since they're being used in the preparation
anyway so the resulting acid wouldn't be significantly contaminated. Worst case, it needs to be redistilled, which isn't a bad idea anyway to remove
NO<sub>x</sub> The result is clean glassware and clean nitric acid, a win-win in my book. This also works wonders for stained stir bars,
one nitric acid prep and they're good as new. You could probably put the addition funnel in place of a column, and it would be subject to all of the
acid vapors which would hopefully oxidize the sulfur. |
I just tried this out yesterday on an a round bottomed flask that got a splattering of gelled up/burned Phenyl Salicylate syrup.
I had previously tried out hot Xylenes, Acetone, Ethanol, HCl, the works. No dice.
The second the Nitric Acid vapour front hit the stuff though, it liquefied and dribbled down into the
KNO3/HNO3/H2SO4 mixture, where it promptly disappeared in a puff of CO2.
In short, I can confirm that this cleaning method definitely works on the most stubborn of stains.
"The chemists are a strange class of mortals, impelled by an almost insane impulse to seek their pleasures amid smoke and
vapor, soot and flame, poisons and poverty; yet among all these evils I seem to live so sweetly that may I die if I were to change places with the
Persian king" - Johann Joachim Becher, 1635 to 1682.
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morsagh
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| Quote: Originally posted by nezza | | Hi. I have an acid solution containing antimony(III) and (V). Is there some way of reducing antimony(V) to (III) and no further or a way of separating
the two species. |
Ascorbic acid should work for reduction
(Edit: added context)
[Edited on 7-1-2016 by zts16]
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Texium
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Threads Merged
1-7-2016 at 12:07 |
Romix
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Heating wire
Please recommend alloy to use as a resistive heating wire.
I tried fat Ni-Chrome wire, from socket. It melted on halfs.
In the place were touched wood.
If placed correctly, will it last?
[Edited on 5-7-2016 by Romix]
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Texium
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Threads Merged
4-7-2016 at 16:40 |
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