[777888]

List all entities initally present (break to ions if possible) in the following mixtures and identify all possible oxidizing and reducing agents:

1) An aqueous chlorine solution is added to a phosphorous acid solution.
-Why can't H3PO3 break into ions H+, PO3(2-) (there is no PO3(2-) in both OA and RA side in the redox table)

2) Iodine solution is added to a basic mixture containing manganese(IV) oxide.
-Can MnO2 break into ions?

3)A potassium dichromate solution is added to an acidic iron(II) nitrate solution.
-Are these the correct entities?
K+    Cr2O7(2-)    H+    H2O    Fe(2+)    NO3(-)

Thank you!

[Donaldson Tan]

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[777888]

Actually, these are the questions left over that I didn't get it! I put my problem below the question!

[777888]

Can someone teach me how to know that H3PO3, MnO2 are insouble? (PO3(3-) is not in the solubility table, I can only find PO4(3-) there)

[Donaldson Tan]

Can someone teach me how to know that H3PO3, MnO2 are insouble? (PO3(3-) is not in the solubility table, I can only find PO4(3-) there)

solvation is spontaneous when |hydration energy| exceeds |lattice energy|

[777888]

When it says chlorine solution, does it mean Cl-(aq) or Cl2(aq)? Similarly, iodine solution refers to I-(aq) or I2(aq)?

For example,
""An aqueous chlorine solution"" is added to a phosphorous acid solution.

Thanks for your *delete me*

[Donaldson Tan]

aqueous chlorine solution refer to Cl₂ (aq). It is actually an equilibrium mixture of chlorine, chloride and chlorate(I), because chlorine disproportionates in water. aqueous iodine exhibits similar property

[AWK]

 (PO3(3-) does not exists. H3PO3 is a diprotic acid, ie it can exchange only two protons during neutralization.
In solution of H3PO3 only (H+), H2PO3(-) and HPO3(2-) exist

[777888]

(PO3(3-) does not exists. H3PO3 is a diprotic acid, ie it can exchange only two protons during neutralization.
In solution of H3PO3 only (H+), H2PO3(-) and HPO3(2-) exist

But there is only H3PO3 in my redox table, but no PO3(3-), H2PO3(-) and HPO3(2-).. But I need to copy the half reactions from the redox table for the strongest oxidizing and reducing agent. So does that mean in the question,
 "An aqueous chlorine solution is added to a phosphorous acid solution"
The species initally present would be: Cl2, H2O, H+, H3PO3 ?  
INSTEAD OF: Cl2, H2O, H+, PO3(3-) ? :help:

[777888]

But there is only H3PO3 in my redox table, but no PO3(3-), H2PO3(-) and HPO3(2-).. But I need to copy the half reactions from the redox table for the strongest oxidizing and reducing agent. So does that mean in the question,
 "An aqueous chlorine solution is added to a phosphorous acid solution"
The species initally present would be: Cl2, H2O, H+, H3PO3 ?  
INSTEAD OF: Cl2, H2O, H+, PO3(3-) ? :help:

Just to make sure if I get the right idea!

[AWK]

H3PO3 is a weak acid, hence only a few percent of H3PO3 dissociates. Though in solution exist such a species, as Cl2 (Cl(-) HClO H3O(+),CLO(-)), H2O, H3PO3 (H3O(+) H2PO3(-)) you can assume that only Cl2 and H3PO3 exist in solution for the search in redox tables.