What is meant by the conjugate acid-base pair? Find the conjugate acid/ base for the following species:

HNO2, CN-, HClO4, F-, OH-, CO32-and S2-

Consider the following acid-base reaction:

HCl+ H2O ⇌ H3O++ Cl-


HCl is an acid because it donates a proton to water (H2O) and H2O is a base because it accepts a proton from H2Oand hence is a base. Thus, there are two acid-base pairs in the reaction. These are HCl-Cl- and H3O+ -H2O. These acid-base pairs are called conjugate acid-base pairs.



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