The water leaving as steam has undergone a physical change from a liquid state to a gaseous one. No chemical change has occurred because it is still H2O.
Basic explanation:
H2O(liquid) + heat <===> H2O(gaseous)
Water passes from a liquid form to a gaseous form through evaporation. By definition, any change in the state of matter is a physical change.
Evaporation Process
When the H2O molecule is heated (excited), physical reactions occur:
- excitement (disorder increase, molecules are increasingly kegeling)
- breaking of the hydrogen bridges/connections between the "O" (oxygens) and "H" (hydrogens), liberating them from their attractive forces through the process of gasification.
This involves a change of state of the water. Before, during, and after the boiling, it remains water. So, since the substance doesn't change its character, the boiling of water is a physical change.
Boiling is a physical change.
When water boils, it is a physical change.
Boiling water is a physical change because it does not change the chemical composition of the water.
Boiling water is physical change.
Boiling of water is a physical process, a change of phase.
vaporization
When water boils, it is a physical change.
Boiling and evaporation are physical changes.
It is a physical change.
The boiling point is a physical property of a substance. It is the temperature at which the vapor pressure of the liquid is equal to the atmospheric pressure, causing the liquid to change into a gas phase.
Boiling water in a kettle is a physical change. This is because the change is reversible, and it involves a phase transition from liquid to gas without changing the chemical makeup of water molecules.