A solution of a substance ‘X’ is used for white washing.

(i) Name the substance ‘X’ and write its formula.

(ii) Write the reaction of the substance ‘X’ named in (i) above with water.



(i) We know that slaked lime (Ca(OH) 2 ) is used for whitewashing .


The solution of slaked lime (Ca(OH) 2 ) is formed by reaction of Quicklime (CaO) and Water (H 2 O).


Hence, the substance ‘X’ is Calcium Oxide / Quicklime and its formula is CaO .


(ii) The reaction of ‘X’ with water is given as 

CaO(s) + H 2 O(l) → Ca(OH) 2 (aq)

  1. Class 10
  2. Chapter 1 Class 10 - Chemical Reactions and Equations (Term 1)

About the Author

CA Maninder Singh's photo - Founder at Teachoo
CA Maninder Singh
CA Maninder Singh is a Chartered Accountant for the past 11 years and a teacher from the past 11 years. He teaches Science, Accounts and English at Teachoo