hi.
i just want to how MQ-2 identify different kind of gas, is there some kind of technique used in the module that is why it is able to detect different kind og gas?? if you know something pls tell me.. it would be really helpful.
It does not identify an unknown gas typically. It is for detection of any of a group of "combustible" gases.
Are you asking how specific the detection is and whether there are gases that will interfere with it? Or, are you asking the mechanism by which SnO2 detects the gas?