Which one of the following processes involve chemical reactions?

(A) Storing of oxygen gas under pressure in a gas cylinder

(B) Liquefaction of air

(C) Keeping petrol in a china dish in the open

(D) Heating copper wire in presence of air at high temperature

 

Answer

Chemical Change vs Physical Change-01.jpg

A physical change is the one in which the chemical properties of a substance do not change

No chemical change is observed when we store oxygen gas under pressure, or during liquefaction of air or when petrol is kept open in a china dish.

 

However, when we heat a copper wire in the presence of air, copper oxide is formed .

The reaction is as follows:

Reaction of Copper with Oxygen - Teachoo.jpg


So, the correct option is (d) heating copper wire in presence of air at a high temp

  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