symboom
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Sodium Carbonate and Aluminum reaction
The reaction by hot sodium carbonate and aluminum is very odd to me the reaction produces hydrogen gas
NaCO3 + Al --> Al3(OH)2 + H2 and CO2?
Is this correct
At room temperature it is not noticeable of a reaction
Could be used in a diy aluminum battery maybe
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Eddygp
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The above equation is neither balanced, nor does the "trialuminium dihydroxide" exist... you magically obtain hydrogen atoms out of nowhere and there
is no sodium at the end either.
As for the reaction, aluminium can't reduce sodium cations...
What are your sources/what reaction did you have in mind?
there may be bugs in gfind
[ˌɛdidʒiˈpiː] IPA pronunciation for my Username |
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Fulmen
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The main reaction is between water and aluminum: 2 Al + 6 H2O-> 2 Al(OH)3 + 3 H2
The sodium carbonate simply attacks the protective layer of Al2O3 that forms on aluminum in contact with air, allowing it to react with water.
We're not banging rocks together here. We know how to put a man back together.
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RogueRose
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The Al reaction in a base, be it Na2CO3 or NaOH (both in hot water) is it the same?
This is quoted from another thread:
http://www.sciencemadness.org/talk/viewthread.php?tid=4832&a...
Quote: Originally posted by 12AX7  |
| Quote: | Al + Na2CO3 + H2O => Nothing happens. You just get a solution of Na2CO3 with pieces of aluminium in it...At least this is what I got when I tried
it 2 minutes ago.
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If the aluminum oxide layer is removed (mercury amalgam could be used), the aluminum will reduce the H2O, leaving Na2CO3 in solution and Al(OH)3 in
suspension. It should react slowly, since Na2CO3 is basic and will dissolve a small amount of aluminum (not much, since CO3-- is stronger than AlO2-,
correct?).
At high temperatures, the aluminum will reduce carbonate to carbide, releasing sodium as vapor at this temperature. This would be written: 3Na2CO3(l)
+ 10Al(l) = Al4C3(s) + 3Al2O3(l) + 6Na(g).
( (l) is liquid, (s) solid, (g) gas. Na2CO3 and/or Al may be gas at the required temperature, and I'm not sure if Al4C3 will decompose to Al(g) +
C(s).)
This reaction is probably not self-sustaining. However, the analogous reaction using sulfate or nitrate instead of carbonate, proceeds quickly.
Tim |
I'm wondering what the resulting Al compound will be if Na2CO3 is used and what if NaOH is used. Also, how fast is the base used up?
This was brought to my attention by a guy who says he uses carbonate and Al as a hydrogen generator for glass blowing. I was wondering if CO2 was
evolved at all but it doesn't seem like it is.
I'm wondering which of the by products of either using carbonate or hydroxide is usable or non-toxic and which would be the better to use for H2
generation.
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Chemetix
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As a sort of tangent to the OP's reaction, could a high temperature reaction take place to place produce sodium?
3Na2CO3 + 2Al -> Al2O3 + 6Na +3CO2
I'm intuiting this would take place at about 600- 800C, and looks like a fairly clean way of producing Na.
ahem...stoics!
[Edited on 28-3-2017 by Chemetix]
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j_sum1
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Sounds intriguing. How do the thermodynamics work out for that one? (I'm on my phone and can't look up details atm.)
If it does work it is a clever technique.
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Harristotle
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Make sure you use anhydrous Na2CO3 !!
decahydrate is a lot of water (an 18:10.6 ratio of water to carbonate)
H.
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Chemetix
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Henri Étienne Sainte-Claire Deville and the Deville process at 1200C....just makes sodium aluminate....bugger!
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Alkemist
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Hehe. Please don't take offense to this but the op's equation reminded me of my own equations for the first month or so of freshman organic chem. With
no absolutely chem experience and having been out of school for almost 10 years, the first month was a bit overwhelming to say the least....I also
apologize for contiributing nothing of substance to the thread.
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AJKOER
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Here is an extract of my prior comment on this forum outlining the chemistry in my opinion:
"Caution with Na2CO3, a boiling aqueous solution of Washing Soda behaves like NaOH, and readily attacks Aluminum utensils causing pitting!
I have verified this with Al foil and boiling Na2CO3 heated in a microwave.
The action of water on Na2CO3, I could express by the reversible reactions:
Na2CO3 + H2O = NaOH + NaHCO3
NaHCO3 + H2O = NaOH + H2O + CO2
and with heating, the escape of CO2 moves the reaction to the right. This is confirmed by a reference to quote:
"In aqueous solution, carbon dioxide production begins at room temperature and decomposition of NaHCO3(aq) is essentially complete if the solution is
brought to boiling."
Link: http://antoine.frostburg.edu/chem/senese/101/inorganic/faq/c...
Contributing would be the introduction of Al, which reacts/removes NaOH, also moving the reaction to the right.
Interestingly, in a cold solution, there is no evidence of any reaction."
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Booze
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| Quote: Originally posted by Fulmen | The main reaction is between water and aluminum: 2 Al + 6 H2O-> 2 Al(OH)3 + 3 H2
The sodium carbonate simply attacks the protective layer of Al2O3 that forms on aluminum in contact with air, allowing it to react with water.
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That reaction is not possible. That reaction is what an alkali metal does with water, like sodium or potassium.
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myristicinaldehyde
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| Quote: Originally posted by Booze | | Quote: Originally posted by Fulmen | The main reaction is between water and aluminum: 2 Al + 6 H2O-> 2 Al(OH)3 + 3 H2
The sodium carbonate simply attacks the protective layer of Al2O3 that forms on aluminum in contact with air, allowing it to react with water.
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That reaction is not possible. That reaction is what an alkali metal does with water, like sodium or potassium. |
I strongly disagree. Aluminium does react with water, when without an oxide coating (like in presence of Cl- or OH-, or with an amalgam)- this I know
from personal experience.
I also found this, if you doubt me. https://www1.eere.energy.gov/hydrogenandfuelcells/pdfs/alumi...
If we don't study the mistakes of the future we're doomed to repeat them for the first time.
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Booze
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I was talking about with just aluminum and water, and nothing else. Trust me, sticking a piece of aluminum in water won't do anything. If you had
something to destroy the oxide coating, then yes it would.
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Texium
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| Quote: Originally posted by Booze |
I was talking about with just aluminum and water, and nothing else. Trust me, sticking a piece of aluminum in water won't do anything. If you had
something to destroy the oxide coating, then yes it would. |
No need to try and cover your ass, it was clear
what you meant. Always double check before you go jumping to statements like "this reaction is impossible" when its clear from reading previous posts
that in the context of the thread it is. You hastily replied without really reading or comprehending Fulmen's whole post.
There are other ways to demonstrate the reaction of aluminum and water as well, such as placing a bit of amalgam with mercury or gallium in water- it
will react vigorously.
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CharlieA
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The original poster's reaction equation does not show water as either a reactant or a product. But since it is not balanced, who knows what the point
is? Postulating possible products requires more information about what reactants/products/reaction conditions are involved. Such a vague question is
not conducive of a specific answer. More details about the original process could lead to a more detailed answer.
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Booze
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| Quote: Originally posted by zts16 | | Quote: Originally posted by Booze |
I was talking about with just aluminum and water, and nothing else. Trust me, sticking a piece of aluminum in water won't do anything. If you had
something to destroy the oxide coating, then yes it would. |
No need to try and cover your ass, it was clear
what you meant. Always double check before you go jumping to statements like "this reaction is impossible" when its clear from reading previous posts
that in the context of the thread it is. You hastily replied without really reading or comprehending Fulmen's whole post.
There are other ways to demonstrate the reaction of aluminum and water as well, such as placing a bit of amalgam with mercury or gallium in water- it
will react vigorously. |
I think we have different definitions of vigorous. I have placed gallium in water, and it is very clear that it is oxodising, but nothing else,
really.
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Texium
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Once again you failed to actually read my post. I described placing an amalgam of aluminum with either mercury or gallium in
water, not gallium alone. You've once again made the point that I was trying to stress in my last post- you need to fully read and comprehend other
peoples' posts before making a statement that is completely irrelevant to the discussion. Read. Think. Post (or don't post, if you realize that you
have nothing to contribute).
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Melgar
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| Quote: Originally posted by Booze | | I think we have different definitions of vigorous. I have placed gallium in water, and it is very clear that it is oxodising, but nothing else,
really. |
You tried to correct someone with wrong information. Now stop playing dumb, and go back and take your public shaming like a man!
The idea is that sodium carbonate could remove aluminum's passivating layer by forming CO2 and this:
https://en.wikipedia.org/wiki/Sodium_aluminate
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Booze
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| Quote: Originally posted by Melgar | | Quote: Originally posted by Booze | | I think we have different definitions of vigorous. I have placed gallium in water, and it is very clear that it is oxodising, but nothing else,
really. |
You tried to correct someone with wrong information. Now stop playing dumb, and go back and take your public shaming like a man!
The idea is that sodium carbonate could remove aluminum's passivating layer by forming CO2 and this:
https://en.wikipedia.org/wiki/Sodium_aluminate |
What do you mean? If I was wrong about gallium's reaction with water, please correct me. I would be interested to hear what it does.
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Booze
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| Quote: Originally posted by zts16 | | Once again you failed to actually read my post. I described placing an amalgam of aluminum with either mercury or gallium in
water, not gallium alone. You've once again made the point that I was trying to stress in my last post- you need to fully read and comprehend other
peoples' posts before making a statement that is completely irrelevant to the discussion. Read. Think. Post (or don't post, if you realize that you
have nothing to contribute). |
I don't understand what you said. A mixture of gallium or mercury? Are you saying that I need both mercury and gallium, or just one?
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Melgar
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| Quote: Originally posted by Booze | | I don't understand what you said. A mixture of gallium or mercury? Are you saying that I need both mercury and gallium, or just one?
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http://en.wikipedia.org/wiki/Amalgam_(chemistry)
Since gallium melts at 30˚C, its alloys are also commonly referred to as "amalgams".
[Edited on 3/29/17 by Melgar]
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