The Henderson-Hasselbalch equation is used in situations where both undissociated acids and their conjugate bases are present in a solution. This situation can occur by adding the conjugate base to a solution of a weak acid or by partially neutralizing the weak acid with a strong base. Mixtures of an undissociated weak acid and its […]
When a weak acid is dissolved in water, the acid will undergo ionization. The ionization of a weak acid, HA, in water can be expressed as: $$ HA+H_2O⇄H^++A^- $$ Four species are present in the solution of the weak acid at equilibrium: HA, A−, H+, and OH−. To calculate the concentrations of the four species […]
When a strong acid (e.g., HCl) is placed in water, the acid ionizes completely as: $$ HCl+H_2O→H^++Cl^- $$ Three species are present in the aqueous solution of the strong acid: H+, OH–, and Cl–. H+, generated from HCl, suppresses the ionization of H2O. This leads to the lower concentration of H+ in water than the […]
The hydrogen ion concentration of a solution varies from approximately 1 in a 1 M solution of a strong acid to about 1×10-14 in a 1 M solution of a strong base, and the calculations often become unwieldy. To alleviate this difficulty, Sörensen suggested a simplified method of expressing hydrogen ion concentration. He established the […]