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Amos
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@zts16: It has been my experience that large amounts of radiant heat at lower temperatures are more efficient than the smaller and more concentrated
flame of a bunsen burner. The best way for me to make completely charcoal black cupric oxide is in a pan on the stove. If you can't use a pan, make a
rigid container out of aluminum foil and stick it on there. You could also use the oven, it doesn't require phenomenal temperatures. Bunsen burners
for me have typically been terrible at properly heating anything other than the layer of material in direct contact with the walls of my crucible.
[Edited on 9-14-2014 by No Tears Only Dreams Now]
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Texium
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Alright, thanks for the advice, I'll try using my hotplate. It worked (on accident) in the past, but this time I wanted to make sure that it fully
decomposed, and my Bunsen burner was already set up for something else. Interesting how that works... you'd think that the burner would work fine for
an amount as small as what I was using.
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Amos
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Quote: Originally posted by zts16  | | Alright, thanks for the advice, I'll try using my hotplate. It worked (on accident) in the past, but this time I wanted to make sure that it fully
decomposed, and my Bunsen burner was already set up for something else. Interesting how that works... you'd think that the burner would work fine for
an amount as small as what I was using. |
I know, it's infuriating for me that it doesn't. Don't forget to stir the cupric oxide often! And maybe wash and filter it when you're done if that
doesn't work.
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bbartlog
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| Quote: Originally posted by No Tears Only Dreams Now | ... cupric oxide is in a pan on the stove. If you can't use a pan, make a rigid container out of aluminum foil and stick it on there.
[Edited on 9-14-2014 by No Tears Only Dreams Now] |
This *probably* won't cause a catastrophe, but nonetheless this is bad advice. Don't put copper compounds in an uncoated aluminum container. Odds are
good you will reduce the copper and end up with aluminum compounds where once you had a container.
The less you bet, the more you lose when you win.
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Amos
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| Quote: Originally posted by bbartlog | | Quote: Originally posted by No Tears Only Dreams Now | ... cupric oxide is in a pan on the stove. If you can't use a pan, make a rigid container out of aluminum foil and stick it on there.
[Edited on 9-14-2014 by No Tears Only Dreams Now] |
This *probably* won't cause a catastrophe, but nonetheless this is bad advice. Don't put copper compounds in an uncoated aluminum container. Odds are
good you will reduce the copper and end up with aluminum compounds where once you had a container. |
At 200 degrees C or so, and in the absence of moisture, with an insoluble compound? Aluminothermic reactions need temperatures in the thousands to
ignite.
[Edited on 9-14-2014 by No Tears Only Dreams Now]
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AlphaDecay
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About making nitric acid: This guy distilled nitric acid (KNO3 + H2SO4) with a retort http://www.youtube.com/watch?v=TpWwBxsyJok&feature=youtu...
Perhaps a 25cm long side arm distillation flask could do the same?
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AlphaDecay
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Does anyone know the reactions involved in Benedict's test? http://en.wikipedia.org/wiki/Benedict%27s_reagent
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gdflp
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Quoting that wikipedia article, "the cupric ion (complexed with citrate ions) is reduced to cuprous ion by the aldehyde group (which is oxidized), and
precipitates as cuprous oxide, Cu2O".
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arkoma
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quick question--aromatic aldehydes generally soluble in MeOH? specifically http://en.wikipedia.org/wiki/3-Acetyl-6-methoxybenzaldehyde
"We believe the knowledge and cultural heritage of mankind should be accessible to all people around the world, regardless of their wealth, social
status, nationality, citizenship, etc" z-lib
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DraconicAcid
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Should be.
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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TheChemiKid
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Are there alternatives to ethanol for extracting capsaicin?
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gdflp
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Acetone or methanol should work as well.
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arkoma
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This paper shows decent results with acetone
"We believe the knowledge and cultural heritage of mankind should be accessible to all people around the world, regardless of their wealth, social
status, nationality, citizenship, etc" z-lib
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bismuthate
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Can compounds, say KNO3, still decompose while in solution? If so it must be harder to do so right?
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Brain&Force
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It depends on the compound, redox potential, and pH, but yes. Are you looking at a specific compound?
At the end of the day, simulating atoms doesn't beat working with the real things...
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bismuthate
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Ferrous oxalate complexes mostly.
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Brain&Force
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What do you call a solvent that can dissolve polar and nonpolar compounds, such as methanol and ethanol? Is there a special word for them?
At the end of the day, simulating atoms doesn't beat working with the real things...
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DraconicAcid
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I'd call them polar organic solvents.
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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Crowfjord
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@Brain&Force: maybe you're thinking of amphiphilic/amphipathc? These words are synonymous and usually refer to things like surfactants or
phospholipids, but they mean "likes both." I'm not sure if they would apply to methanol or ethanol, though; those are usually just considered polar,
protic solvents.
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AlphaDecay
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I have found a thread talking about the synthesis of ZnCO3, but I still have doubts about using Na2CO3 or NaHCO3... Has anyone tried this synthesis?
http://www.sciencemadness.org/talk/viewthread.php?tid=18167#...
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Brain&Force
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| Quote: Originally posted by Crowfjord | | @Brain&Force: maybe you're thinking of amphiphilic/amphipathc? These words are synonymous and usually refer to things like surfactants or
phospholipids, but they mean "likes both." I'm not sure if they would apply to methanol or ethanol, though; those are usually just considered polar,
protic solvents. |
Yes, that's what I was talking about. The thing is, on the Sciencemadness Wiki we have a few solvents classed as both polar and nonpolar solvents,
which seems contradictory.
At the end of the day, simulating atoms doesn't beat working with the real things...
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gdflp
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Can you use 10% ammonia when using the hypochlorite ketazine process to make hydrazine sulfate, and just increase the volume proportionately, or do
you need to use 20% or higher concentrations of ammonia?
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Amos
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Yeah I have quite a bit of nice flour-fine zinc carbonate(I think it is, anyway) made with just simple baking soda and zinc chloride. It decomposes in
a torch flame to the oxide, turning yellow with the heat, so if your end-goal is the oxide, then whatever I have works for it.
[Edited on 9-26-2014 by No Tears Only Dreams Now]
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Amos
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| Quote: Originally posted by gdflp | | Can you use 10% ammonia when using the hypochlorite ketazine process to make hydrazine sulfate, and just increase the volume proportionately, or do
you need to use 20% or higher concentrations of ammonia? |
According to NurdRage this works, so if you trust him then go ahead. You'll probably get a lower yield, though.
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gdflp
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When did he say that? I think by "lower concentrations" he meant 20%, though I could be wrong.
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