Question 9.
Is cloud formation a physical change or a chemical change? Explain.
What kind of change is shown by tearing of paper?
Why is the souring of milk a physical change or a chemical change?
Cloud formation is a physical change.
Explanation: It takes place due to the physical transformation of the liquid phase to the gaseous phase of water by evaporation and condensation and is a part of the water cycle.
Physical change
The souring of milk is classified as a chemical change. This is because it results in the production of sour-tasting lactic acid. In this process, new substances (lactic acid) have been formed