Trying to Convert an Equation into an Ionic Equation

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The discussion centers on converting the equation PbSO4(aq) >>> Pb(s) + PbO2(aq) + SO42-(aq) into an ionic equation. It highlights the confusion regarding the oxidation states of lead, noting that Pb2+(aq) can convert to Pb4+(aq) without maintaining the same charge, which is essential in metal oxidation. The participants emphasize the importance of understanding the context of lead in a lead-acid battery, where both PbSO4 and PbO2 are solids in concentrated sulfuric acid. They suggest starting with a formal non-ionic equation and incorporating H2O and H+ to facilitate the conversion to an ionic equation. The complexity of the process is acknowledged, indicating that it requires careful consideration and practice.
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Homework Statement



PbSO4(aq) >>> Pb(s) + PbO2(aq) + S042-(aq)

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The Attempt at a Solution



PbSO4(aq) must be Pb2+(aq) SO42-

But PbO2(aq) seems to have to be Pb4+(aq) + 2O-(aq)

How can Pb go from Pb2+(aq) to Pb4+(aq); doesn't it have to keep the same charge?
 
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Both PbSO4 and PbO2 are solids.

Note that there is no way to balance the equation as written - charge is only on one side.
 
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Borek said:
Both PbSO4 and PbO2 are solids.

Note that there is no way to balance the equation as written - charge is only on one side.

I'm sorry. I just noticed in brackets it says that they are soluble because they are in an acid solution.
 
Then the box is simply not true - please read about how the lead battery works. Its construction is based on the fact both these substances are solids immersed in the concentrated sulfuric acid.
 
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Borek said:
Then the box is simply not true - please read about how the lead battery works. Its construction is based on the fact both these substances are solids immersed in the concentrated sulfuric acid.

Thanks for the reassurance, it must be another mistake in my textbook.
 
When you say it has to keep the same charge, no it does not - you also have Pb metal in there which has another charge (0). In fact not having the same charge is of the essence in oxidation of metals isn't it? and in the lead-acid battery you do have three levels of lead oxidation involved.
It might help to try the formal non-ionic equation first, but you can't do it with what you've got in yours - you also need H2O.
Then try to get the ionic one. Include H+. You are also allowed to use HSO4-. Spend a little time to try and get it, because if you do that first and then look it up it might click whereas if you only look it up you will say yes yes and forget it by next time. It is quite tricky.

There is an account of this quite important application in links here: https://www.physicsforums.com/threa...ipitation-of-unknown-ion.790077/#post-4980286
 
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