Abstract
This review systematizes the essential data on alkalide solutions called also alkali metal solutions or blue solutions, i.e. solutions of the salts containing alkali metal anions (M-). It focuses particularly on the formation and decomposition of potassium potassides as well as on the equilibrium and non-equilibrium reactions occurring with the participation of solvated electrons (e-), potassium anions (K-) and potassium cations complexed crown ethers (K+Ln, where n = 1 or 2). An explanation is proposed of the puzzling constancy of [e-] while [K-] decreases in apparent contradiction of the law of mass action in the reaction with an oxidant or during the self-decomposition of the solution.
Keywords: Potassium Potassides, Tetrahydrofuran Solution, alkalide solutions, law of mass action, self-decomposition