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==Acidity of the Salt==
==Acidity of the Salt==
The salt which forms may have a [[pH]] of its own due due to its components being [[conjugate acid]]s and [[conjugate base]]s. The conjugate acid of a strong base and the conjugate base of a strong acid are weak, and hence will not dissociate. However, the conjugates of weak acids/bases are strong bases/acids, and hence will undergo a hydrolysis reaction with water to form and acid/base. The general rule is:
*A strong acid and a strong base will form a neutral salt
*A strong acid and a weak base will form an acidic salt (will react with water to form an acid)
*A strong base and a weak acid will form a basic salt (will react with water to form a base)
For instance, a strong acid and weak base reaction may proceed as such:
2HCl<sub>(aq)</sub> + Fe(OH)<sub>2(aq)</sub> -- 2H<sub>2</sub>O<sub>(l)</sub> + FeCl<sub>2(aq)</sub>
The iron component of the iron chloride may then undergo a hydrolysis reaction with water, such that:
Fe<sup>2+</sub> + H<sub>2</sub>O<sub>(l)</sub> -- Fe(OH)<sub>2(aq)</sub> + H<sup>+</sup><sub>(aq)</sub>
As the iron hydroxide is a weak base it will not dissociate to any great extent and hence will not raise the pH of the water greatly, however this hydrolysis reaction causes an excess of hydrogen ions, which result in the pH of the water being lowered hence causing it to be acidic. As the chloride ion is a weak base it will not react with water, hence producing an acidic salt.
The same process applies for basic salts, however the products will contain an excess of OH<sup>-</sup> and a weak acid, causing the water to become basic.
[[Category:Chemistry]]
[[Category:Chemistry]]