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Question
An alkali metal A gives a compound B (molecular mass = 40) on reacting with water. The compound B gives a soluble compound C on treatment with aluminium oxide. Identify A, B and C and give the reaction involved.
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Solution
Alkali metal sodium when reacting with water gives a chemical compound sodium hydroxide. When sodium hydroxide is treated with aluminium oxide gives a soluble compound sodium aluminate.
Hence, A is sodium, B is sodium hydroxide and C is sodium aluminate.
`"Al"_2"O"_3("s") + 2"NaOH"("aq") -> 2"NaAlO"_2("aq") + "H"_2"O"("l")`
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