Experiments on the chemical behaviour of argon and helium

Historical and Introductory. —The discoverers of argon, Rayleigh and Ramsay, showed that when subjected to very severe chemical treatment the gas failed to combine with any other element. Later on Collie and Ramsay also showed that helium resembled argon in being chemically inactive. Moissan and Berthelot both carried out experiments with argon, but neither obtained real proof of any power of argon to enter into chemical combination. It has always been assumed that if union of argon or helium with any other element occurred the action would be strongly endothermic, and experiments have always been framed in such a way as to impart to the system a plentiful supply of energy.