Strengths of acids and bases acid-dissociation or ionization constant

5 Strengths of acids and bases acid-dissociation (or ionization) constant 

The Br0nsted-Lowry view of acids and bases suggests that the Strengths of acids can be compared by measuring their relative tendencies to release a proton to a common base (taken to be water). Thus, if we represent an acid by HA and consider its reaction with water 

The dissociation constant for the conjugate base A of HA is given by the equilibrium constant for the forward reaction of 

The strongest acid that can exist in water is H (aq), because any material that releases a proton more readily than water will completely ionize in water to form H+(aq) for example, HCl, H2SO4, and HNO3 are 100% ionized in water. Similarly, OH (aq) is the strongest base that can exist in water, because any base that is a stronger proton acceptor will remove protons from the water to become what is called completely protonated [e.g., S (aq), 0 (aq) and H (aq) are 100% protonated in water]. 

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