Question

Why do all bases in water give oh- ions

Answer 1

These particular substances produce hydroxide ions (OH−) in aqueous solutions, and are thus classified as Arrhenius bases. For a substance to be classified as an Arrhenius base, it must produce hydroxide ions in an aqueous solution. In order to do so, Arrhenius believed the base must contain hydroxide in the formula. This makes the Arrhenius model limited, as it cannot explain the basic properties of aqueous solutions of ammonia (NH3) or its organic derivatives (amines).[1] There are also bases that do not contain a hydroxide ion but nevertheless react with water, resulting in an increase in the concentration of the hydroxide ion.[2] An example of this is the reaction between ammonia and water to produce ammonium and hydroxide.[2] In this reaction ammonia is the base because it accepts a proton from the water molecule.[2] Ammonia and other bases similar to it usually have the ability to form a bond with a proton due to the unshared pair of electrons that they possess.