YT2095 Posted December 28, 2005 Posted December 28, 2005 since the group 1 elements can be substituted for Hydrogen, I got to thinking about Sodium Aluminate, and the possibility of Hydrogen Aluminate. NaAlO2 to HAlO2. after a google search, it came up with nothing at all usefull, Does this compound or Can this compound actualy exist?
the tree Posted December 28, 2005 Posted December 28, 2005 I can't think of any good reason why [math]\cf{HAl02}[/math] shouldn't exist, my guess is that it's either to tricky to make and doesn't occur naturally or that it is completely useless and boring so no-ones written about it.
YT2095 Posted December 28, 2005 Author Posted December 28, 2005 well I was thinking along the lines of KMnO4, and that the K can be replaced with the H making HMnO4 (permanganic acid) there`s a few others that will work similarly, so would HAlO2 be something crazy like Aluminic acid? can a Ferric acid exist? according to google no, not really I`m either overlooking something dead obvious, or there`s a slight Glitch in Chemistry naming conventions? I`m probably missing something.
RyanJ Posted December 28, 2005 Posted December 28, 2005 since the group 1 elements can be substituted for Hydrogen' date=' I got to thinking about Sodium Aluminate, and the possibility of Hydrogen Aluminate. NaAlO2 to HAlO2. after a google search, it came up with nothing at all usefull, Does this compound or Can this compound actualy exist?[/quote'] I've never heared of the second one but there is a compound called Aluminium Oxyhydroxide with a formula AlO(OH) - the same as your by the looks of things As for Sodium Aluminate it does exist yes but I have no information on converting it too AlO(OH)... Cheers, Ryan Jones
YT2095 Posted December 28, 2005 Author Posted December 28, 2005 sodium aluminate does, yeah. my questioning is can the Na be replaced with H to make HAlO2? or even an Ammonium ion? we have things like D block "Ates" like Ferrate, Zincate, Chromate, Manganate etc.... any one of these with a preceeding Hydrogen makes the coresponding acid, does the same apply with Aluminates though?
RyanJ Posted December 28, 2005 Posted December 28, 2005 sodium aluminate does' date=' yeah. my questioning is can the Na be replaced with H to make HAlO2? or even an Ammonium ion?we have things like D block "Ates" like Ferrate, Zincate, Chromate, Manganate etc.... any one of these with a preceeding Hydrogen makes the coresponding acid, does the same apply with Aluminates though?[/quote'] It should be possible but I'm shure the formula would be: AlHO2 because Al would need too be +3, H would bneed too be +1 and O would be -2 Seeing that Al likes too be in a +3 state it should be stable too - would it be possible too do with some sort of displacement reaction? Cheers, Ryan Jones
YT2095 Posted December 28, 2005 Author Posted December 28, 2005 it seems as you go across the periodic table from left to right, the occurance of possible "Ates" increases to inevitability. starting with a select few of the transition metals and so forth. with the exception of Oxygen and the nobel gasses naturaly. to the far left there`s no such "Ates" or possibilities of Acids occuring, Hydrogen Potassiumate would be plain ridiculous! LOL so since sodium will react with the Al to form the aluminate, what if Hyrogen did the same, could an "Aluminic acid" be formed?
RyanJ Posted December 28, 2005 Posted December 28, 2005 so since sodium will react with the Al to form the aluminate' date=' what if Hyrogen did the same, could an "Aluminic acid" be formed?[/quote'] Hmm.... [ce]2Al + 3H2 -> 2AlH3[/ce] Or.... [ce]2Al + 2O2 + H2 -> 2AlHO2[/ce] I'd think the first is more likley... I think it would probably form a Hydride in that case but I do not know for shure and yes I would like too see Hydrogen Potassiumate Cheers, Ryan Jones
budullewraagh Posted December 28, 2005 Posted December 28, 2005 yes you can indeed replace the Na with H. it's all related to conjugate acidity/basicity: the reason H2SO4+MX-->HX+MSO4 (where m=metal cation and x=anion) is because HSO4- is a really weak conjugate base and metals tend to be really weak conjugate acids. consider: H2SO4+CsF-->HF+CsHSO4 Cs+ is not going to want electrons, ever, so it will stay as far away from them as possible. the H+ is a much stronger conjugate acid, and actually does make legitimate bonds with things (nonmetal hydrides, metal hydrides, organics, etc) and so it will bond to the stronger conjugate base (F-) and yes, it will also ionize to some degree. on the other hand, the Cs+ and HSO4- really don't show any significant covalent character because HSO4- is such a weak conjugate base and Cs+ is such a weak conjugate acid. so to form HAlO2, you need to find a mineral acid whose anion is a weaker base than AlO2-. take, for instance, H2SO4. so H2SO4+NaAlO2-->NaHSO4+HAlO2 i would think that HAlO2 would show more of a basic character than an acidic character
YT2095 Posted December 28, 2005 Author Posted December 28, 2005 Hmm... from the Looks of that then, it doesn`t seem that such an "Acid" could actualy exist alone as a Stand-alone product then. maybe a bit like HMnO4 can`t really exist as a single Stand-alone product?
woelen Posted December 28, 2005 Posted December 28, 2005 HAlO2 indeed does exist. It is a white insoluble powder, but it can better be written as AlO(OH). Most elements for compounds with OH-groups directly attached to the element. However, the properties of these compounds strongly depend on the element. In general one can state that when going from left to right in the periodic table the properties shift from basic to alkaline and also when going from low oxidation state to high oxidation state, one goes from basic to acidic. Some examples: LiOH Be(OH)2 B(OH)3 CO(OH)2 NO2(OH) The left of the first row contains the strong base LiOH and the right contains the strong nitric acid. NaOH Mg(OH)2 Al(OH)3 SiO(OH)2 PO(OH)3 SO2(OH)2 ClO3(OH) The left of the second row contains lye as strong base and sulphuric acid and perchloric acid as strong acids. Phosphoric acid is an intermediate acid. Silicic acid is very weak. Increase of oxidation state: Cr(OH)2 basic Cr(OH)3 amphoteric (can act as base, but also as acid) CrO2(OH)2 acidic (chromic acid) So, the presence of OH-groups can lead to bases, acids and to amphoteric compounds.
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