Which of the following is/are the example/examples of chemical change?
1. Crystallization of sodium chloride
2. Melting of ice
3. Souring of milk
Select the correct answer using the code given below.(2014)
a) 1 and 2 only
b) 3 only
c) 1, 2 and 3
d) None
ANswer: B
Chemical changes occur when a substance combines with another to form a new substance. Crystallization of sodium chloride is not a chemical as water of crystallization can be lost to get salt again . Similarly melting of ice is reversible .However souring of milk is a chemical change as it is not reversible and a new compound is formed.
