Question

What change is observed on dipping a litmus paper in aqueous solution of MgO

Answer 1

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Answer 2

If we dip a litmus paper in aqueous solution of MgO, then we observe that the red litmus paper changes to blue color.  

We need to assume that gO has certain solubility linked with it.

The O2- ion will receive a proton from the water molecule for producing OH-.

Hence, it is now having certain basicity linked with the solution.