Invisibility Cloaks and Hot Reactions: Applying Infrared Thermography in the Chemistry Education Laboratory

Abstract

Infrared (IR) thermography renders invisible infrared radiation with intuitive coloration in images and videos taken of objects, reactions, and processes. Educators can take advantage of this technology to extend students’ sensory perception of chemical reactions or processes that absorb or release heat in rich detail. In theory, IR thermography can be applied essentially universally for such analysis given that any change in thermal energy must result in, or from, the change of potential energy due to the interactions among atoms, molecules, and photons. Through the use of IR thermography, students can visualize otherwise invisible evidence of what is occurring on the molecular level in a variety of chemical process such as evaporative cooling, phase change, dissolution, titration, and enzymatic reactions. While not new, IR cameras are rapidly becoming affordable with models that connect easily with smartphones and tablets. The price decrease has opened the door for large-scale implementation in the chemistry education laboratory. We report here several laboratory activities and best practices that will facilitate the exploration of specific chemistry concepts through the use of infrared thermography, as well as integration of this technique into existing general chemistry laboratory courses.

Exploring the Maker Culture in Chemistry: Making an Affordable Thermal Imaging System for Reaction Visualization

“…While the quality of the image is low compared to a commercially available thermal imaging camera, − the educational value rivals that of the commercial ones. Due to the low resolution of the thermal infrared sensor, which consists of only 64 pixels, it can only image the general heat profile of simple objects with defined shapes, making the glass beaker an ideal candidate.…”

“…Since most undergraduate thermodynamic experiments involve measuring changes in temperature, the ability to visualize this process can bring a new element to the topic of thermodynamics, allowing for the better engagement of students . Recently, the incorporation of thermal imaging cameras into the chemistry laboratory has allowed students to better understand the concepts of exothermic and endothermic reactions. − In fact, most visual learners will benefit from this approach, advocating for its importance in the undergraduate laboratory setting. However, most commercially available thermal imaging cameras are expensive, ranging from hundreds to thousands of dollars, often an inaccessible amount for many undergraduate laboratories. − Therefore, in bridging this affordability gap, we present in this technology report an open-source thermal imaging system that can be assembled for under $100 USD.…”

“…Recently, the incorporation of thermal imaging cameras into the chemistry laboratory has allowed students to better understand the concepts of exothermic and endothermic reactions. − In fact, most visual learners will benefit from this approach, advocating for its importance in the undergraduate laboratory setting. However, most commercially available thermal imaging cameras are expensive, ranging from hundreds to thousands of dollars, often an inaccessible amount for many undergraduate laboratories. − Therefore, in bridging this affordability gap, we present in this technology report an open-source thermal imaging system that can be assembled for under $100 USD. This camera is based on Arduino microcontroller architecture, a popular open-source microcontroller in the Maker community.…”

Infrared Thermography as an Operando Tool for the Analysis of Catalytic Processes: How to Use It?

“…As a measurement technique, IR thermography operating principle is based on the detection of the IR radiation emitted by every object with a temperature above 0 K [2]. The measured radiation can be directly correlated with the temperature of the object, allowing for a precise and fast determination of the temperature [3]. The methodology is widely employed outside the field of catalysis, for example for the determination of temperature in medical applications or for the analysis of heat losses in buildings [4][5][6].…”

Using an Infrared Camera to Visualize a Simple Demonstration of Changing the Internal Energy of a System

“…The thermal imaging cameras used to be quite expensive, but recently, small, portable, and relatively inexpensive ones are readily available and have been widely used for body temperature monitoring, especially during the COVID-19 pandemic. Infrared cameras have been applied in thermochemistry-related education, and their potential in chemistry education could be extended more in the future. − …”