Question

A metal give a compound b with molecular mass of 40 the compound c on teratment with al oxide indentify a,b.,c

Answer 1

Let the atomic weight of alkali metal A be x. When it reacts with water, it forms a compound B having molecular mass 40. Let the reaction be

According to the question,

x + 16 + 1 = 40 (Given)

x = 40-17 = 23

It is the atomic weight of Na (sodium).

Therefore, the alkali metal (A) is Na and the reaction is

So, compound B is sodium hydroxide (NaOH).

Sodium hydroxide reacts with aluminium oxide (Al2O3) to give sodium aluminate (NaAlO2). Thus, C is sodium aluminate (NaAlO2). The reaction involved is Al2O3+