Is sodium chloride a mixture?
Answer:
Sodium chloride solid is not a mixture. It is a \(\text{pure substance…}\) It cannot be physically separated into its components, \(\mathrm{Na}^{+}\) and \(\mathrm{Cl}^{-} \text {. }\) It would require energy input, and that is clearly not a physical means.
However, if for some reason, you meant \(\mathrm{NaCl}(a q) \ldots\) then sodium chloride IN WATER is a mixture, occurring through the physical dispersion of a liquid solvent amongst the ions, \(\mathrm{Na}^{+}\) and \(\mathrm{Cl}^{-},\) that dissociate in solution, surrounding them to separate them from each other.
As a further note, the ions were held together by electrostatic attractions in a lattice, so no chemical change actually occurred!
And in water, this gives:
(This qualifies as a mixture, since evaporation allows reformation of sodium chloride solid again, thus separating the components, \(\mathrm{NaCl}\) and \(\mathrm{H}_{2} \mathrm{O}\) via physical means. It is known as a homogeneous mixture.)