acid-base+hydrolysis

Acid-Base Hydrolysis
A **hydrolysis reaction** is one that involves water. Acids and bases that are aqueous in nature will undergo reactions with water.

Here is the general equation for an __acid hydrolysis reaction__, where A = any anion:

HA (aq) + **H 2 O (l) --> H 3 O + (aq)** + A - (aq)

The bold section of the reaction is the most important part - water is acting as a base (proton acceptor), and forming the hydronium ion (H 3 O + ), which is going to be the common denominator in all acid hydrolysis reactions. The anion loses an oxidation state (it lost a positively charged proton).

Here is one example, using nitric acid:

HNO 3 (aq) + **H 2 O (l) --> H 3 O + (aq)** + NO 3 - (aq)

Watch an animation of acid dissociation here.

A __base hydrolysis reaction__ follows the chemical equation below (where B is any base):

B (aq) + **H 2 O (l) --> OH - (aq)** + HB + (aq)

Again, the bold section of the above equation is the common factor in all base hydrolysis reactions. Water is now acting as an acid (donating a proton), and will form the hydroxide ion (OH - ). The base will gain an oxidation state with the addition of the positively charged proton.

Look at the following example involving the sulfate ion:

SO 4 2- (aq) + **H 2 O (l) --> OH - (aq)** + HSO 4 - (aq)

Try some example problems on this worksheet: