"Like dissolves like" is an
expression used by chemists to remember how some solvents work. It refers to
"polar" and "nonpolar" solvents and solutes. Basic example:
Water is polar. Oil is non polar. Water will not dissolve oil. Water is polar.
Salt (NaCl) is ionic (which is considered extremely polar). Like dissolves like,
that means polar dissolves polar, so water dissolves salt.
Polar substances WILL
dissolve in Polar substances
Non-polar substances WILL
dissolve in nonpolar substances
Non-polar
substances WILL NOT dissolve in polar
substances.
Look
at the layers in this video
Molecule-Ion Attractions
This
is how water and ions attract. The hydrogen's of water align themselves towards
the negative ion (anion), surround it and takes it away. If the ion is a
positive ion (a cation) the oxygen of the water align themselves towards the
ion, surround it and takes it away.
