DIY Arduino calorimeter: Converting commercial thermally insulated coffee-cups into precision isobaric calorimeters

Area of Science:

• Chemistry Education
• Physical Chemistry
• Laboratory Instrumentation

Background:

• Traditional thermochemistry education often relies on outdated or expensive equipment.
• Existing educational calorimeters may lack digital monitoring capabilities, leading to errors and reduced engagement.
• Professional-grade calorimeters are prohibitively expensive for most educational institutions.

Purpose of the Study:

• To design and validate a low-cost digital calorimeter for educational purposes.
• To create an accessible platform for teaching thermochemistry across various scientific disciplines.
• To improve the reproducibility and engagement of laboratory experiments in thermochemistry.

Main Methods:

• Repurposing a commercial thermal container into a constant-pressure system.
• Utilizing a Dallas DS18B20 digital temperature sensor interfaced with an Arduino UNO board.
• Developing open-source software for automated data acquisition and real-time visualization.

Main Results:

• The Arduino-based calorimeter, costing approximately $30 in components, demonstrated reliable thermometric response.
• Validation experiments showed stable equilibrium detection and enthalpy values consistent with literature.
• The system offers improved reproducibility and eliminates manual reading errors compared to traditional methods.

Conclusions:

• This open-hardware digital calorimeter democratizes access to thermochemistry education.
• It provides an affordable and effective tool for hands-on learning in chemistry, engineering, and life sciences.
• The calorimeter serves as a platform for interdisciplinary training in electronics, programming, and automation.