CHAPTER 4 CHANGES AROUND US
A change is a process by which a material turns into something different that it was before. A tiny sapling becoming into a huge tree is an example of a change. The season turning from summer to winter is also a change.
Types of changes:
If we can reverse a change i.e. get back the material that we started with, it is called a reversible change.
If we cannot get back the material that we started with, the change is called non-reversible or irreversible.
Ways to bring a change:
Boiling Is when beyond which if water is heated, it starts to evaporate i.e. it changes from liquid to vapour.
This is the process by which water vapour cools down and changes into liquid state.
This is the process by which conversion takes place from liquid state to solid state.
This is the process in which conversion takes place from solid state to liquid state.
These changes can all be categorized into reversible and non-reversible changes. We’ll learn later about how the changes around us can be grouped.