22 points!
in this unit we have talked about the differences between chemical and physical changes, take a look at the following images below and decide which one is representing a chemical change, and explain how you know it is a chemical change in 2-3 sentences.

The second picture is the representation of chemical change.

Explanation:

The first picture shows the physical change because in this case heat is supplied to the molecules and they move away from each others without changing the composition. It is just like the transformation of liquid water into gas. when the water is heated it evaporated without changing the composition. While the second image shows the chemical change because two substance are combined and form a new substance. Which is different from the reactants.

Chemical:

The changes, that occur due to change in the composition of a substance and result in a different compound is known as chemical change.

These changes are irreversible

These changes occur due to chemical reactions

Example:

Combustion of fuel or wood: that oil or wood convert into energy, CO2 and ash in case of wood

Boiling of egg: that change the chemical composition of protein in the egg

Physical Change                                                                                              

The changes that occur only due to change in shape or form but their chemical or internal composition remain unchanged.

These changes were reversible.

They have same chemical property.  

Example

Water converting to Ice

Water converting to gas

In this water molecule remain the same only they rearrange themselves that change its state of mater not composition