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The MQ-2 gas sensor module is suitable for detecting LPG, i-butane, propane, methane ,alcohol, Hydrogen, smoke.
Code
In this example we simply connect the AOUT to Analog pin 0 and read in the value and output this via the serial monitor
[cpp]
int sensorValue;
void setup()
{
Serial.begin(9600); // sets the serial port to 9600
}
void loop()
{
sensorValue = analogRead(0); // read analog input pin 0
Serial.println(sensorValue, DEC); // prints the value read
delay(100); // wait 100ms for next reading
}
[/cpp]
Links

Electronic Brick – MQ2 Gas Sensor Brick

CG312 MQ2 Smoke Gas Sensor Module for Arduino (Works with Official Arduino Boards)


