How do you determine if water contains dissolved table salt?

Ok the original question is: A beaker contains a clear, colourless liquid. If it is water, how could you determine whether it contains dissolved table salt, without tasting it. Ok I was thinking because its a chemical change that you would determine the chemical formula, and I thought to write out the chemical equation. If you think that would be the right answer whats the chemical reaction for salt dissolving in water. Thanks.How do you determine if water contains dissolved table salt?
dissolution isn't a chemical reaction.



you could do this

1) measure the conductivity of the water. (or the resistance.. they are reciprocols of each other)

pure water has a resistivity of about 18.2 megaohms.

water + salt has a resistivity much closer to zero ohms. it can conduct electricity quite well.



2) you could evaporate some of the water. if a white solid remains, it had salt in it.



3) you could try precipitating out the chlorine by adding silver nitrate. if a ppt forms.. you probably had table salt in your water



4) you could run it through an ICP.. that should be able to measure sodium and chlorine if it's calibrated to it. But they are rather expensive and complex to maintain and operate.



does that help?How do you determine if water contains dissolved table salt?
Put a salt water fish in it. If the fish does not die by the time the homework is due, then it might be salty. To be sure, boil the water and see if salt remains in the bottom of the beaker after the water boils off (evaporates).



You will be docked points if you forget to take out the salt water fish before boiling the water. Unless of course you want lunch at the same time as chemistry class.



Good luck to you.
boil it or whatever.



if there is salt in it, the water will evaporate and the salt will be left behind.

and this would not be chemical because a chemical reaction produces a color change, precipitate(solid), gas, light/heat.



none of these things were produced which makes it physical.
First if all its not a chemical change....you could check its density or freezing points...salt water is more dense and freezes at lower temps than fresh water