Compound Identification

How can I identify the anion of an unknown solution?

- The possible cations in the solution are Ag, Al, Fe, Mg, Zn (not really important to this part)
- The anions could be either NO3- or Cl-

We're given Na2CO3 and NaOH solutions to do the test.

I'm supposed to use a solubility table to help me as well. My main difficulty is what type of reactions will be produced, and how will I use them to identify the compound...

Surely you have done SOMETHING to help you identify the compound. Something such as adding Na2CO3 and NaOH to each of some solution containing the cations. I would identify the cation first.

Knowing the cation, you KNOW (from the solubility tables) that
AgCl is insoluble. Therefore, if you have Cl the cation will not be Ag.
Frankly, I don't think you can identify the anion given ONLY Na2CO3 and NaOH and no other information. If you can, you're a better chemist than I.

To identify the anion of an unknown solution, you can perform a series of chemical tests to observe the reactions and use a solubility table to determine the compound.

In this case, you are given Na2CO3 and NaOH solutions, which can be used as a reagent to identify the anions. Let's break down the steps:

1. Test with Na2CO3 solution:
- Add a small amount of the unknown solution to a test tube.
- Add a few drops of Na2CO3 solution to the test tube and observe any changes.

The possible reactions that can occur are:
a) AgCl (Ag+ and Cl-) precipitates from the solution as white curdy precipitate.
b) No visible reaction with NO3-.

By observing the presence or absence of a precipitate, you can infer whether the anion is Cl- (precipitate forms) or NO3- (no precipitate forms).

2. Test with NaOH solution:
- Add a small amount of the unknown solution to a test tube.
- Add a few drops of NaOH solution to the test tube and observe any changes.

The possible reactions that can occur are:
a) Al(OH)3 (Al3+ and OH-) precipitates from the solution as a white gelatinous precipitate.
b) Fe(OH)3 (Fe3+ and OH-) precipitates from the solution as a reddish-brown precipitate.
c) No visible reaction with Cl- or NO3-.

By observing the presence or absence of a precipitate, you can determine the possible cations present in the solution. However, the goal here is to identify the anion, so the observations from the previous test with Na2CO3 are more relevant.

Remember, it is important to consult a solubility table to verify the solubility of the potential precipitates in each reaction. From the solubility table, you can determine which compound is likely to precipitate based on the reaction observed.

By carefully observing the reactions and consulting the solubility table, you can determine whether the anion in your unknown solution is Cl- or NO3-.