When salt is added to ice, ice starts to melt. We can see that with our eyes. But what does this process look like with a thermal imaging camera that can see the differences in temperature?
In this Beauty of Science video, Getting Cold (with thermal imaging), a high-resolution thermal imaging camera captures five spontaneous endothermic processes, “any process which requires or absorbs energy from its surroundings, usually in the form of heat.” See liquid evaporation, ice melting, urea dissolving, the reaction between barium hydroxide and ammonium chloride, and the well-known reaction between baking soda and vinegar.
Here’s a brief explanation of how thermal imaging works: All objects emit infrared energy (heat) as a function of their temperature. The infrared energy emitted by an object is known as its heat signature. In general, the hotter an object is, the more radiation it emits. A thermal imager (also known as a thermal camera) is essentially a heat sensor that is capable of detecting tiny differences in temperature. The device collects the infrared radiation from objects in the scene and creates an electronic image based on information about the temperature differences. Because objects are rarely precisely the same temperature as other objects around them, a thermal camera can detect them and they will appear as distinct in a thermal image.
Below: “The dissolving of sodium hydroxide, the dilution of concentrated sulfuric acid, the hydration reaction between concentrated sulfuric acid and paper, the neutralization reaction between hydrochloric acid and sodium hydroxide, and the reaction between sodium metal and water.”
Find more videos at Envisioning Chemistry.
Plus, more thermal imaging: Electrified Pickle and what happens when beavers are reintroduced to England?