Borax (Na₂B₄O₇·10H₂O) was locally heated in a test tube using infrared radiation to observe the release behavior of its water of crystallization.
Infrared irradiation causes the crystallization water contained within the solid to separate and be released as liquid water, which subsequently turns into water vapor and generates bubbling.
This video demonstrates that infrared local heating supplies energy to the interior of a solid, allowing internal reactions and dehydration to proceed even without reaching melting.
It serves as a suitable demonstration for understanding the characteristics of non-contact internal heating occurring in a short time.
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