An element A reacts with water to form a compound B which is used in white washing. The compound B on heating forms an oxide C which on treatment with water gives back B. Identify A, B and C and give the reactions involved.

An element A reacts with water to form a compound B which is used in w

1.	An element A reacts with water to form a compound B which is used in white washing. The compound B on heating forms an oxide C which on treatment with water gives back B. Identify A, B and C and give the reactions involved.
Answer» SOLUTION :A is calcium it reacts with WATER to form calcium hydroxide which is used in WHITE washing so B is `Ca(OH)_2`. `Ca(s)+2H_2O(l)to Ca(OH)_2(aq)_B+H_2(g)` On HEATING compound B, i.e., calcium hydroxide it forms calcium oxide i.e., C `Ca(OH)_2to^(Heat)CaO_c+H_2O`