The invention relates to a gas analyzing device (1) which comprises at least one ion mobility spectrometer (2). Said gas analyzing device (1) also comprises an energy supply device (50) interacting with a reaction chamber (5) of the ion mobility spectrometer (2) which is designed to manipulate the density of free reactant ions in the reaction chamber (5) by supplying energy. The invention also relates to a method for analyzing gas by means of a gas analyzing device according to the ion mobility spectrometry.
