Question

solution of substances X is used for white washing (1) name the substance X and write its formula (2) write thr reaction of substance x with water

Answer 1

The substance X is calcium oxide CaO
Reaction: CaO + H2O = Ca(OH)2

Answer 2

Hi friend
substance X is Cao (calcium oxide)
reaction:-
CaO      +    H2O→Ca(OH)2(slaked lime)
calcium       water   calcium 
oxide                       hydroxide
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