The older type (1) and newer type (2) Silica gel subjected to a moisture test.
Type (1). Blue, changes to orange when moisture is absorbed.
Type (2). Orange, changes to bluish green when moisture is absorbed.
Si-Gel is used to prevent moisture ingress in high voltage oil circuit breakers and transformers.
It is also used in packaging for electronic equipment.
A lot of heat is generated during the exothermic process.
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