XhmikosR
Harmless
Posts: 3
Registered: 5-9-2006
Member Is Offline
Mood: No Mood
|
|
Questions about Inorganic Chemistry
Hi guys, I'm new here and I have some questions about Inorganic Chemistry because I need them for an essay in my University. I'd appreciate any help.
So, here it is.
1) Stereochemical structure of Tl4 (8-).
2) Reaction Na2SiO3 + HCl --> ?
and what' s the name of the product of this reaction.
3) Reaction of: S + NaOH --> ?
4) Reaction of: TeO2 + C --> ?
5) Reaxtion SO2 + H2S --> ?
|
|
|
unionised
International Hazard
Posts: 5104
Registered: 1-11-2003
Location: UK
Member Is Offline
Mood: No Mood
|
|
Just out of idle curiosity, do you plan to get us to answer the questions when you sit exams?
Does your university have a library? Did you try reading a book?
|
|
|
XhmikosR
Harmless
Posts: 3
Registered: 5-9-2006
Member Is Offline
Mood: No Mood
|
|
If I was able to visit my library believe me I wouldn't bother any of you. But I'm not in my University this period and this stuff I'm asking for are
not in the book. I can't find them and I've tried a lot. The book for this class is the worst ever and that's why I asked for your help.
|
|
|
12AX7
Post Harlot
Posts: 4803
Registered: 8-3-2005
Location: oscillating
Member Is Offline
Mood: informative
|
|
Should've spent your money at a better school methinks!
|
|
|
XhmikosR
Harmless
Posts: 3
Registered: 5-9-2006
Member Is Offline
Mood: No Mood
|
|
Yeah that would be great but in my country we don' t have private Universities; we only have public and the quality of books isn't the best yet...
[Edited on 5-9-2006 by XhmikosR]
|
|
|
woelen
Super Administrator
Posts: 7977
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
I'll try to help you, but my answers will not be complete:
1) ?????
------------------------------------------------------------------------------
2) The answer to this is not simple at all. The simplified reaction mechanism is the following:
Na2SiO3 + 2HCl ----> 2NaCl + SiO2 + H2O
In fact, when you mix solutions of these two, you get some brittle white or almost transparent precipitate, which mostly is written as SiO2. This is
the main constituent of plain white sand, silicon dioxide.
In reality, things are more complex. These compounds only exist in their ionized form in solution, so it would already be better to write:
SiO3(2-) + 2H(+) --> SiO2 + H2O, the NA(+) and Cl(-) ions are just spectator ions.
But also here, the story does not yet end. The brittle precipitate is not pure dry SiO2, but it is a form of hydrous SiO2. In reality, it is a complex
network of Si-O-Si strings, with many =O and -OH groups attached all over the place. Something like (SiO)xOy(OH)z, with net average formula SiO2.nH2O.
Only by very good rinsing and strong heating of the precipitate, one really obtains SiO2.
------------------------------------------------------------------------------
3) What school are you at? Is this supposed to be simple elementary chemistry? I cannot believe that this reaction is asked for a real beginner. But
anyway, I'll try to explain what happens.
The element sulphur disproportionates under the right conditions. In hot solutions of NaOH the sulphur, which is in oxidation state 0 will split in
compounds with negative oxidation state and other compounds with positive oxidation state and the sulphur then will dissolve.
There is reaction with the OH(-) ions of the NaOH, again Na(+) is just spectator ion:
4S + 6OH(-) ---> 2S(2-) + S2O3(2-) + H2O
The sulphur disproportionates to sulfide and thiosulfate. There are also side reactions, where the sulphur disproportionates to sulfide and sulfite.
3S + 6OH(-) ---> 2S(2-) + SO3(2-) + H2O
But if excess sulphur is formed, then the sulfite reacts to thiosulfate also:
S + SO3(2-) ----> S2O3(2-)
If a lot of excess sulphur is present, then the liquid becomes golden yellow, and polysulfides are formed:
S + S(2-) ---> S2(2-)
2S + S(2-) ----> S3(2-)
...
4S + S(2-) ---> S5(2-)
Finally, the liquid contains a very complex mix of all kinds of (poly)sulfide ions, thiosulfate ions and possibly some sulfite ions.
------------------------------------------------------------------------------
4) I'm not sure about that. It might be TeO2 + C --> Te + CO2.
It might also be TeO2 + 2C --> Te + 2CO. Probably both at the same time. But I have no detailed knowledge about Te-chemistry, so its best to try
to get an answer from someone also.
------------------------------------------------------------------------------
5) This reaction also is VERY complicated and depends on the state of the compounds. If both gases are mixed and are perfectly dry, then no reaction
occurs. If the gasses are a little humid, then the main reaction will be:
2H2S + SO2 --> 3S + 2H2O, but there are many side-reactions, by no means will you get pure S and water.
When the gases are dissolved in water, then you get an increadibly complex reaction. It is called "Wackenroder's reaction", and a whole bunch of
(poly)thionates, free sulphur, thiosulfate and a lot more of stuff is formed. No single reaction equation can be given for this. I suggest you do a
search on Wackenroder. The following link gives a detailed description. You see, big articles can be written on this, and people have done PhD
researches on this seemingly simple reaction: http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_00...
[Edited on 6-9-06 by woelen]
|
|
|
ayumichen
Harmless
Posts: 6
Registered: 21-8-2006
Member Is Offline
Mood: No Mood
|
|
1.Are u sure that it is right????
3.3S + 6NaOH ==> 2Na2S + Na2SO3 + 3H2O
Sulphur dissolves in hot sodium hydroxide.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
