Heating chamber for a heating furnace , comprising: an electrically-conductive wall ; a sample reception area ; a nozzle area ; a first electrical connection area ; and a second electrical connection area , wherein the sample reception area and the nozzle area are each surrounded by the wall , wherein the sample reception area and the nozzle area are arranged one behind the other along a longitudinal axis that extends centrally and said sample reception area and nozzle area are embodied in fluid communication with one other, and the sample reception area comprises a larger cross-sectional area than the nozzle area , wherein the first and the second electrical connection area are arranged adjacent to opposite ends of the heating chamber relative to the longitudinal axis of the heating chamber and are electrically connected to the wall , characterized in that the heating chamber is embodied in such a manner that an electric current that is produced by means of applying an electric voltage to the first and second electrical connection area flows through the wall in such a manner that a heating capacity that is produced by said electrical current is equal to or greater in the nozzle area than in the sample reception area , wherein the first and the second electrical connection area are arranged in the radial direction more remote from the longitudinal axis than a part of the wall that surrounds the nozzle area , and wherein the heating chamber is embodied in such a manner that the current that is produced between the first and the second electrical connection area is directed predominantly radially inwards towards the part of the wall that surrounds the nozzle area . an electrically-conductive wall ; a sample reception area ; a nozzle area ; a first electrical connection area ; and a second electrical connection area , wherein the sample reception area and the nozzle area are each surrounded by the wall , wherein the sample reception area and the nozzle area are arranged one behind the other along a longitudinal axis that extends centrally and said sample reception area and nozzle area are embodied in fluid communication with one other, and the sample reception area comprises a larger cross-sectional area than the nozzle area , wherein the first and the second electrical connection area are arranged adjacent to opposite ends of the heating chamber relative to the longitudinal axis of the heating chamber and are electrically connected to the wall , characterized in that the heating chamber is embodied in such a manner that an electric current that is produced by means of applying an electric voltage to the first and second electrical connection area flows through the wall in such a manner that a heating capacity that is produced by said electrical current is equal to or greater in the nozzle area than in the sample reception area , wherein the first and the second electrical connection area are arranged in the radial direction more remote from the longitudinal axis than a part of the wall that surrounds the nozzle area , and wherein the heating chamber is embodied in such a manner that the current that is produced between the first and the second electrical connection area is directed predominantly radially inwards towards the part of the wall that surrounds the nozzle area . <EOS>