An alkali metal A gives a compound B (molecular mass=40) on reacting with water. The B gives a soluble compound C on treatment with aluminium oxide. Identify A,B, and C and give the reaction involved.
It is given that an alkali metal A gives a compound B whose molecular mass is 40. The molecular mass of NaOH is 40:
23 × 1 + 16 + 1 = 40
The alkali metal is Na (A). When Na reacts with water, it forms NaOH (B). The reaction is:
When sodium hydroxide (B) reacts with aluminum oxide, it gives sodium alumninate (NaAlO2). Hence, compound C is sodium alumninate. The reaction is:
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