[cryptocrafter]

Hello everyone! I'm like really struggling with chemistry for no reason right now because I'm kind of an idiot. I have no idea how to write and balance reactions. I have simple high school honors chemistry, and my teacher likes to give us about 25 homework problems a night. Anyway these equations are messing me up big time. I have a "reference packet" that describes what each type of reaction creates based on if its synthesis, decomposition, etc. So for example we have H₂(SO₃) decomposes. According to my packet, oxyacids decompose as (NM)O + H₂O. So I thought I would just right SO+ H2O, but that becomes impossibly hard to balance. I looked it up and its supposed to be SO₂ + H₂O, but how am I supposed to know that? Charges should be irrelevant since its covalent right?

Or there's Fe(OH)₃ decomposes. So metal hydroxides decompose into MO + H₂0 So I write FeO + H₂O and then I'm supposed to balance it but once again, it seems impossibly hard so I look it up to see where I went wrong. Well its ionic so charges matter I guess so Fe has a charge of 2- and O 2+ so fe₂o₂ but then its STILL too hard. Apparently iron decides to be 3 in this case, and I was just supposed to know that somehow. Its supposed to be Fe₂O₃ + H₂O. WHY? I don't understand. I know its a transition metal so it can have different charges but why does it choose 3. Now that I think about it, charges and subscripts aren't even the same thing. Please help me. Sorry I'm so bad at this. I promise I'm not a total idiot I have all A's I just do a bad job at paying attention and my teacher is crazy.

[Borek]

I think you are misreading the general ideas presented by by the "reference packet" (could be it is ambiguous). Looks to me like what it is telling you in these two examples is that the acids and hydroxides decompose into water and an oxide - but not necessarily monooxide. Which oxide is produced depends on the initial valence of the main atom in the decomposing compound. In Fe(OH)₃ Fe is apparently trivalent and it has to retain this valence after the decomposition, hence the product is Fe₂O₃.

Decomposition of the sulfurous acid to SO+H₂O is not "impossibly hard" to balance. It is impossible to balance, period.