Inorganic salts like sodium and potassium fluoride can be exploited as nucleophilic fluoride sources. These salts are much easier to store and handle than HF and so tend to be more widely used by chemists. The type of chemistry conducted with these salts is wide ranging; for example, as well as using them to add fluoride directly to a molecule, they also serve as useful activating reagents in reactions like Hiyama cross couplings. As fluoride sources, sodium and potassium fluoride can be used for the addition of fluoride in nucleophilic substitution reactions.