After hydrogen fluoride, KF is the primary source of the fluoride ion for applications in manufacturing and in chemistry. Potassium fluoride is a chemical compound that is the primary source of fluoride ion after hydrogen fluoride. KF is the molecular formula of potassium fluoride. It is an alkali halide and occurs naturally as the rare mineral carobbiite. Potassium fluoride is the chemical compound with the formula KF. It is a colourless or white crystalline compound with no odour. Structure, properties, spectra, suppliers and links for: Potassium fluoride, 7789-23-3. Solutions of KF will etch glass due to the formation of soluble fluorosilicates, although HF is more effective.