Concentration expressed in moles of solute dissolved per
unit volume (dm3 or liter)
of solution is also referred to as the molarity
(represented by ‘M’)
of the solution.
In other words, molarity
of the NaCl solution is 0.171, or
stated another way 0.171
M is the concentration of NaCl, or the NaCl solution is 0.171 molar.
It can often be represented by square brackets around the
substance under consideration.
–eg.
[NaCl] represents the concentration of sodium chloride.
So, the
above particulars (the concentration of the salt solution) can be expressed
thus:
–[NaCl] = 0.171 mol/dm3
Now, if we
were to continue to add NaCl to the solution the concentration changes,
it increases.