molarity is defined as the number of moles dissolved in 1 L of solution .2 mol of NaOH has been dissolved in a volume of 3 L.
we need to then find the number of NaOH moles dissolved in 1 L.
Molarity = number of moles / volume in L
Molarity = 2 mol / 3 L = 0.67 mol/L
Therefore molarity of NaOH - 0.67 M
