How to derive multiple gasses from a gas sensor which only has 3 sensing elements?

I'm looking at the datasheet of the MiCS-6814 from Sensortech, and it says it measures Ammonia, Carbon Monoxide, Ethanol, Hydrogen, Iso-Butane, Methane, Nitrogen Dioxide, Propane but it has only 3...

10 October 2019 6,724 6 View