Gas detector

void setup() {
pinMode(A0, INPUT);//sensor data input line
pinMode(2,OUTPUT);//power led
pinMode(7,OUTPUT); //led
pinMode(9,OUTPUT); //led
pinMode(10,OUTPUT); //led
pinMode(11,OUTPUT); //led
Serial.begin(9600); //serial monitor
}


float val;
void loop() {
 val=analogRead(A0);
 Serial.println(val);

digitalWrite(2,HIGH);//power led on

if(val>500){//these values can be chnaged for your needs (ex:500)
 
  digitalWrite(7,HIGH);
}
else {
  digitalWrite(7,LOW);
}
 if (val>430){
  digitalWrite(9,HIGH);
}
else {
  digitalWrite(9,LOW);
}
if (val>400){
  digitalWrite(10,HIGH);
}
else {
  digitalWrite(10,LOW);
}

 if (val>385){
  digitalWrite(11,HIGH);
}
else {
  digitalWrite(11,LOW);
}







 

}