A combustible gas sensor including a first sensing element having a catalyst and a heating element and electronic circuitry in operative connection with the heating element of the first sensing element to change a temperature thereof between a temperature above a temperature to catalyze oxidative combustion and a temperature at which the catalyst is substantially inactive to catalyze oxidative combustion of a plurality of gas analytes of interest. The electronic circuitry being configured to determine a species of at least one of the plurality of gas analytes of interest from a first, dynamic output of the combustible gas sensor while the temperature of the first sensing element is changing. The electronic circuitry further being configured to determine a concentration of the species from a second output of the combustible gas sensor.