On whether potassium acetate is a weak base

Whether potassium acetate is a weak base or not, its properties must be investigated. Potassium acetate is composed of potassium ions and acetate ions. Potassium ions do not hydrolyze in aqueous solutions, because their corresponding potassium hydroxide is a strong base and is completely ionized in water.

Acetate ions are not. Acetate is a weak acid, and its ionization constant is small. Acetate ions will undergo hydrolysis in water, and the hydrogen ions ionized by water will increase the concentration of hydroxide ions in the solution. The equation for hydrolysis is: $CH_ {3} COO ^{-} + H_ {2} O\ rightleftharpoons CH_ {3} COOH + OH ^{-}$ 。

Looking at the hydrolysis reaction, it can be seen that the solution is alkaline. However, the generation of alkalinity is not due to the direct ionization of a large number of hydroxide ions by potassium acetate, but the hydrolysis of acetate ions. And the degree of hydrolysis is relatively limited. Compared with the direct complete ionization of a large number of hydroxide ions by strong bases such as sodium hydroxide, the alkalinity of potassium acetate solution is weaker.

In summary, although potassium acetate is alkaline, it is a weak base due to its hydrolysis and limited degree of alkali.