[hocktag]

After first considering methods using solubility, I am a little stuck. We are given a small amount of white powder, which is known to be a mixture of sodium chloride and sodium carbonate, and we are to work out the percentage composition by mass. Is it true that thermal decomposition would be viable, because the carbonate would decompose when heated but not the chloride? I had considered this (and I think others are using this method) but how would you distinguish from the unreacted NaCl and the Na2O produced. Is there a better way?

Thanks very much for the help, your time is appreciated!

[DrCMS]

What does sodium carbonate react with that sodium chloride does not?

[hocktag]

Any chloride salt, right? At first I had written this option off as I thought this would result in both provided substances being soluble, and how does that help? But could I use, say, Calcium Chloride and measure the mass of the Calcium Carbonate produced? Thanks for the help.

[Hunter2]

Still the wrong way. Do you know the behavoior of Carbonate in acidic envirement. With this knowledge you can consider to detect your carbonate.

[hocktag]

If an acid, say HCl, was added to the mixture of the solids, how would I distinguish between the two salts in terms of their mass? I understand how to test for, and detect a carbonate through the use of an acid and limewater, but I am missing the point on the separation of the two (or at least the possibility of measuring one through products formed or something). Thanks again for your time.

[Hunter2]

You have the weight of the mixture. You do the titration with acid and get the mass of the carbonate. The difference is the Chloride.