Joy-it sen-mq3 Alcohol/ethanol gas sensor 1 pc(s) Compatible with (development kits): Arduino, Raspberry Pi | Conrad.com
CQRobot Contact Water/Liquid Level Sensor for Raspberry Pi/Arduino. Low Power Consumption, Corrosion Resistance, High Pressure Resistance, High Temperature Resistance and Stable Chemical Properties. : Amazon.com.au
ChemDuino: Adapting Arduino for Low-Cost Chemical Measurements in Lecture and Laboratory | Journal of Chemical Education
Ketosense – An Arduino based ketosis detector – jenslabs
Arduino Breathalyzer Using MQ3 Gas sensor and OLED Display - Electronics-Lab.com