1. It won't balance because you don't have the right formula down. The left side is ok but iron(III) hydroxide is Fe(OH)3,
2. It is a pptn reaction because aq/g/l on the left goes to a solid on the right. However, it ALSO is a redox reaction. Fe on the left is +2 and on the right is +3 so Fe is oxidized. O2 on the left is zero and on the right is -2; therefore, O2 is reduced. Note that the O in FeO is -2 on the left and -2 on the right; it is not involved in the redox part. Having said all of that, I suspect you are to report this as a redox reaction. Although a ppt forms it isn't a typical pptn type reaction.
I am having so much trouble understanding how to classify reactions as precipitation, acid base, or oxidation reduction. In one example in particular, it reads Iron II oxide reacts with oxygen and water to yield Iron III hydroxide. I wrote out the equation as: FeO(aq)+O2(g)+H2O(l)=FeOH3(s). I was thinking it was oxidation reduction but it produces a solid so that got me thinking its a precipitation reaction! Which ultimately got me thinking I really don't understand how to classify them. Also, it's impossible to balance this equation. I've double checked my symbols and I don't know what's going on.
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Oh my goodness! Thank you so much for pointing that out. Two little brackets - and it balanced just fine. Thank you also for explaining that this can be seen both ways, technically. It gives me a little more confidence.
While eating supper it occurred to me that something was amiss about that problem. How do you get an aqueous solution of FeO. FeO is a solid and very little of it will dissolve. This may be one of a series of reactions for the formation of rust. Anyway, I wonder if that should have been FeO(s) and if so then a solid going to a solid will not be a pptn reaction even though the solids are different.
Thank you for that. Chemistry is the most challenging class for me and I am the one that assigned it (aq) because all that still confuses me too. In the original problems, we were just given the words and we need to write the chemical formulas. I get confused about when to use (aq) (s) (l) and (g), well actually (g) is the easy one. Initially I was just using the solubility rules to determine if something would be a solid but then found that's not always correct because when I look back at my instructor's powerpoint, I find she uses (aq) for things that I would call (s) so I find I'm sometimes just giving it my best guess.
Generally you will be right doing it that way. If the material is soluble and you have a liquid solution (such as HCl, H2SO4, HNO3, etc are all in aq solution) so the solubility rules work very well. Yes, gases are easy. If you're mixing solutions that makes it easy, too.
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