Question

Which of the following method is used for preparing a
base?
(1) Burning of metal in air.
(2) Adding water to a metal oxide.
(3) Reaction between an acid and base.
(4) Heating metal carbonate.​

Answer 1

(2) Adding water to a metal oxide

Because metal oxides are basic in nature and when we mix them with water they make the metal hydroxide,that is a base.

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