Question

why is caustic soda used in black utensil​

Answer 1

Answer:

Sodium Hydroxide (Caustic Soda) is a strong base. It is used in metal degreasing and cleaning processes in a wide range of industry applications. Stainless steels types 304 and 316 can be considered resistant below 80 degC, up to the limit of solubility.

Answer 2

If the utensil contains aluminium then your problem would be erosion of the aluminium due to its reaction with the caustic soda.

But be mindful of exposing glassware to a strong caustic solution as the latter will cause erosion and pitting of the glass which could result in considerable damage to expensive glassware.

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Hope it helps you...!!!