Oxides in Aqueous Solution Acidic and Basic Anhydrides

Oxides in Aqueous Solution (Acidic and Basic Anhydrides) 

Some common metal oxides (basic anhydrides) and their corresponding bases. 

The ionic oxides are characterized hy the presence of the oxide ion, 0, that, like the ion, cannot exist alone in aqueous solution. The reaction between the oxide and a water molecule is shown in Equation (11.9)  

Note that the 2— charged oxide attacks and forms a bond with a partially positive hydrogen atom of the water molecule. The subsequent breaking (represented by a discontinuity in the bond) of the O—H bond produces two hydroxide ions. The equilibrium constant for Equation (11.9) is greater than 10, so this reaction lies far to the right. Taking sodium oxide as an example, the full reaction of an ionic oxide with water is represented in Equation (11.10)  

Equation (11.12) shows a specific example starting with sulfur trioxide as the nonmetal oxide that produces sulfuric acid as the oxoacid that in turn dissociates 

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