Project Ideas

Use the pH sensor module and the Arduino to measure the acidity of water before and after CO2 is added to it.

Use a water carbonator like a SodaStream or simply blow into a water bottle with a straw.

Code

const int analogInPin = A0;

int sensorValue = 0;

unsigned long int avgValue;

float b;

int buf[10],temp;

void setup() {

Serial.begin(9600);

}

void loop() {

for(int i=0;i<10;i++)

{

buf[i]=analogRead(analogInPin);

delay(10);

}

for(int i=0;i<9;i++)

{

for(int j=i+1;j<10;j++)

{

if(buf[i]>buf[j])

{

temp=buf[i];

buf[i]=buf[j];

buf[j]=temp;

}

}

}

avgValue=0;

for(int i=2;i<8;i++)

avgValue+=buf[i];

float pHVol=(float)avgValue*5.0/1024/6;

float phValue = -5.70 * pHVol + 21.34;

Serial.print("sensor = ");

Serial.println(phValue);

delay(20);

}