Physical change
All chemical substances consist of one or more elements. Sometimes, changes
occur only in the physical conditions of a substance leaving its chemical
structure unchanged. This is called a physical change.
Physical change examples
A solid piece of ice, if kept at room temperature, absorbs heat from the
environment and gradually melts into liquid water. Again, heating liquid water
up to 100°C will see the water vaporize into the air. Here, all the
molecular formulas of all three – water, ice, and vapor are the same –
H2O.
That means each molecule of them has the same two hydrogen and one oxygen
atoms in them. Therefore, all three substances are the same, only their
physical states are different – ice solid while water is liquid and vapor is
gaseous. This kind of change is called a physical change.
