Solid calcium oxide reacts vigorously with water to form calcium hydroxide accompanied by liberation of heat. This process is called slaking of lime. Calcium hydroxide dissolves in water to form its solution called lime water. Which among the following is (are) true about slaking of lime and the solution formed?

(i) It is an endothermic reaction

(ii) It is an exothermic reaction

(iii) The pH of the resulting solution will be more than seven

(iv) The pH of the resulting solution will be less than seven

(A) (i) and (ii) 

(B) (ii) and (iii)

(C) (i) and (iv) 

(D) (iii) and (iv)

Answer

Slaking of Lime - Teachoo.jpg

Here,

  • Since heat is liberated in the reaction, it is an exothermic reaction .
  • The end product formed is Ca(OH) 2 i.e calcium hydroxide. It is a base , so the pH of the resulting solution will be more than 7.

 

So, the correct answer is (b) - (ii) and (iii)

 

  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