Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: 350chev on October 18, 2009, 01:11:56 AM
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Ok so I am running out of ideas as to how to name this equation. I think I have everything balanced out and ready to go but I guess not :(
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Any ideas? Is it all (aq)?
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The writing looks a bit fuzzy, but from what I can see, you've got two mistakes
1. All nitrates are soluble.
2. H2PO4- is an ion, it doesn't split in half like you've done it.
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The writing looks a bit fuzzy, but from what I can see, you've got two mistakes
1. All nitrates are soluble.
2. H2PO4- is an ion, it doesn't split in half like you've done it.
Yeah webassign makes things complicated :(
Ok so make everything (aq) since all nitrates are soluble. So it should be Pb3H2(PO4)?
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No, lead forms Pb2+.
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NaH2NO3?
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NaH2NO3?
Right but I already have that?
No, lead forms Pb2+.
So it should be Pb3H2(PO4)2? Since its an ionic bond.
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Either webassign uses some completely off convention for entering formulas, or you have no idea what you are doing.
What is formula of sodium nitrate?
What is formula of lead (II) phosphate?
Why do you put H everywhere?
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Either webassign uses some completely off convention for entering formulas, or you have no idea what you are doing.
What is formula of sodium nitrate?
What is formula of lead (II) phosphate?
Why do you put H everywhere?
Na(NO3) is sodium nitrate.
Pb3(PO4)2 is lead(II) phosphate
My TA told me that I was missing multiple hydrogens... I didnt understand why except that maybe some of the compounds were somehow acidic?
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Na(NO3) is sodium nitrate.
NaNO3 will do, no need of () if no repetition.
Pb3(PO4)2 is lead(II) phosphate
OK.
My TA told me that I was missing multiple hydrogens... I didnt understand why except that maybe some of the compounds were somehow acidic?
So you either misunderstood TA or TA was not clear. Sometimes they are needed, but not here. For example there are three different sodium phosphates - Na3PO4, Na2HPO4, NaH2PO4 - but they have also different names (I am not sure what the correct IUPAC names are, probably something like sodium dihydrogenphosphate for NaH2PO4, but don't quote me on that).
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Na(NO3) is sodium nitrate.
NaNO3 will do, no need of () if no repetition.
Pb3(PO4)2 is lead(II) phosphate
OK.
My TA told me that I was missing multiple hydrogens... I didnt understand why except that maybe some of the compounds were somehow acidic?
So you either misunderstood TA or TA was not clear. Sometimes they are needed, but not here. For example there are three different sodium phosphates - Na3PO4, Na2HPO4, NaH2PO4 - but they have also different names (I am not sure what the correct IUPAC names are, probably something like sodium dihydrogenphosphate for NaH2PO4, but don't quote me on that).
Pb(NO3)2(aq)+Na(PO4)(aq)-->Pb3(PO4)2(aq)+Na(NO3)(aq)
So I went over it and came up with this. Now with polyatomics in the equation do I need to balance it? It seems incomplete... Or is this good enough to plug in and submit?
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Pb(NO3)2(aq)+Na(PO4)(aq)-->Pb3(PO4)2(aq)+Na(NO3)(aq)
So I went over it and came up with this. Now with polyatomics in the equation do I need to balance it? It seems incomplete... Or is this good enough to plug in and submit?
This is not balanced - and Na(PO4) is not a formula of a sodium phosphate.
I told you parentheses in NaNO3 are not needed.
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Pb(NO3)2(aq)+Na(PO4)(aq)-->Pb3(PO4)2(aq)+Na(NO3)(aq)
So I went over it and came up with this. Now with polyatomics in the equation do I need to balance it? It seems incomplete... Or is this good enough to plug in and submit?
This is not balanced - and Na(PO4) is not a formula of a sodium phosphate.
I told you parentheses in NaNO3 are not needed.
Ok I got it right after making a few changes. Thanks for the help.
One thing though. Why does Na(PO4) need () while NaNO3 doesnt?
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NaPO4 does not need parentheses here, but your equation isn't balanced; Sodium phosphate is an ionic compound and thus the charges of the individual ions must be considered. The formula is Na3PO4. Since this is the Undergrad Chemistry forums, I assume you know why parentheses are needed in some cases with ionic compounds...
Had you been writing a net ionic equation for this reaction, parentheses would not be needed as any subscripts would have been moved to being coefficients of the ion.
I hope this helps and I'm sorry if my answer is kind of nonsensical.
It's kind of late where I live :P
Greg
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Parentheses are used to show that a group of atoms is repeated in the molecule.
NaNO3 - OK.
Ca(NO3)2 - two NO3- groups in molecule.
AlPO4 - OK.
Fe3(PO4)2 - two PO43- groups in molecule.
Basically Fe3(PO4)2 can be also written as Fe3P2O8 but you can't see what it is then.