hydroxide ion

…associated with the presence of hydroxide ions (OH⁻) in aqueous solution, and the neutralization of acids by bases could be explained in terms of the reaction of these two ions to give the neutral molecule water (H⁺ + OH⁻ → H₂O). This led naturally to the simple definition that acids…

…triphenylphosphine; whereas hard bases include hydroxide, fluoride, and many oxyanions. The dividing line between the hard and soft categories is not a sharp one, and its theoretical interpretation is obscure. Nevertheless, a surprising amount of factual information can be coordinated on the basis of preferential reactions of hard acids with…

…most common base is the hydroxide ion (OH⁻), which reacts with an H⁺ ion to form a water molecule. H⁺ + OH⁻ → HOH (usually written H₂O)