The pH is a determinant to acidity and basicity of its solution. The pH is calculated as a negative log of concentration of Hydrogen ions in solution. pH= -log (H+) We can find pH of Sodium Hydroxide solution as follows: Concentration of Hydroxide Ion: For a strong base, we expect complete dissociation of molecules so concentration is equivalent to NaOH concentration. (OH+)= 0.1 mol/dm3 Concentration of Hydrogen Ion: For any solution, the product of concentration of hydrogen ions, adn concentration of hydroxide ions is equal to ion product of water= (H20)= (H+)(OH-) 1.00 x 10-14 = (H+)(0.1) (H+)=1.00 x 10-13 Calculate the pH: pH = - log10[1.00 x 10-13] pH=13