|MadSci Network: Chemistry|
I have been explaining to my eighth grade students that it is clear that dissolving is a physical change because although you can't see salt when it dissolves in water, you can taste it. Also, if the salt molcules broke apart you would get atoms of sodium which explodes in water, and chlorine gas which is a poisonous gas. Now I am reading further in my (new) text and reading that NaCl molecules "dissociate" when they dissolve. How is this different from breaking the NaCl molecules apart into sodium metal and chlorine gas? Any suggestions on how to explain this to eighth graders?
Re: How can dissociation of salt when dissolving not be a chemical change?
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