What is the pH of 10-9 M HCl?
Here , [H+] for acid is < 10 -7 { which is not possible }
so,
total [H+] = 10 -7 + 10 -9
= 1.01 x 10 -7
Thus, pH = - log [H+]
= 6.99
Define the degree of ionization.
It is a measure for strength of electrolytes, the electrolytes which have degree of ionization nearly equal to 1 are strong, else are weak.
It is the representation of ratio of molecules disassociated ions to the total number of molecules when put in water. its range is [0,1].