What are some of the key characteristics of unknown sample of an aqueous solutio

Question

What are some of the key characteristics of unknown sample of an aqueous solution containing an ionic compound?

Specific questions:

1. Given that the cation is from Group 1A, what is the identity of the group 1A metal ion in your solution?

2. Given that the ionic compound contains either chloride or hydroxide, how can you determine which? (Two pieces of evidence are required and one must be related to solubility rules)

3. What is the concentration of your solution? (Your unknown sample is known to be about 1 M, but you need to determine the concentration to 3 significant figures using titration. You should plan ahead so that you know approximately what volume of your sample you will need in order to use approximately 25 mL of 0.100 M sulfuric acid for the titration).

How would I go about performing an experiment to determine the answers to these questions.

Explanation / Answer

The only thing i can think of is somehow heating the solution so that it dehydrates and leaves a residue of the compound and then burning that compound to see what the color of the flame is. Since it's group 1 metals the colors should be pretty easy to see and tell apart.

Assuming we can burn away the water and just leave the material remaining we can easily find the unknown. This requires both step 2 and 3 to be completed. The first thing is we know the concentration. So since we know the concentration we can get a specific amount of moles. Lets just assume for the sake of this that you have .1 mol of the solution. We also know if it is a hydroxide or chloride form number 2. Take a look at this and what do you have.
Mols you have of product.
Weight of half of the compound.
So all you need to do from here is weigh the solution. Mass/Mols = molar mass 1
molar mass 1 - (17 or 35? not sure chlorine off the top of my head) = Molar mass of the other half
Molar mass of the other half gives us the molar mass of the element.

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