Is common salt soluble in all types of water?

1 Answer
Nov 12, 2015

Most types of water do so; save for the kind that is already saturated with salt.


#NaCl(s) rightleftharpoons Na^+(aq) + Cl^(-)(aq)#

When we write #Na^+(aq)# we means the aquated sodium ion; this results from the chemical dissolution of salt in a water (i.e. aqueous) solvent. Another way of representing this would be: #[Na(OH_2)_6]^+#. The reaction above is a reversible chemical equilibrium, and on standing the salt would deposit as #NaCl# crystals.

It is worthwhile at home to grow macroscopic crystals of salt. Take a saturated solution (a solution that is in equilibrium with undissolved salt), filter it, and add (precisely) 1 tiny crystal of salt. If evaporation is kept to a minimum (by covering the solution), aqueous salt will precipitate only on the 1 salt crystal that you added. I have grown very large crystals (#2.5xx2.5# #cm#) of salt this way.