Silica Gel

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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