An apparatus for cracking gases with a supply line (1) for a carbon-containing gas, by means of which the gas is capable of being supplied to a first heat exchanger (5, 9) with a fill of a thermal storage mass, a first combustion chamber (6, 8) which is arranged downstream in the direction of flow of the gas and which, in particular, has a supply device capable of being regulated for another oxygen-containing gas, by means of which a partial oxidation of the carbon-containing gas is carried out by the hypostoichiometric supply of oxygen, and a reactor (7) which is arranged downstream of the first combustion chamber (6, 8) in the direction of flow of the gas which has a fill of a catalytically acting material for the catalytic splitting of impurities of the carbon-containing gas. According to the invention a second combustion chamber (6, 8) with a supply device—in particular capable of being regulated—for an oxygen-containing gas, by means of which a partial oxidation of the catalytically prepared carbon-containing gas is carried out by the hypostoichiometric supply of oxygen, is arranged downstream of the reactor (7) in the direction of flow of the carbon-containing gas, and a second heat exchanger (5, 9) with a fill of a thermal storage mass is arranged downstream of this combustion chamber in the direction of flow of the gas, wherein the direction of flow of the carbon-containing gas is capable of being reversed at least in a region which encloses the first and second heat exchanger (5, 9), the first and second combustion chamber (6, 8) and the reactor (7).