A phase change is a physical change. It is not a chemical change.
Physical changes do not alter the chemical composition of a substance, only its physical appearance or state. Examples include changes in shape, size, phase (solid, liquid, gas), or state of matter (melting, freezing, dissolving).
When a liquid reaches boiling point it goes through a phase change, liquid to gas. Phase changes do not change the nature of a chemical so it is a physical change. This physical change can sometimes be caused by a chemical change though.
Boiling is a physical change, not chemical.
chemical
Chemical changes occur when the elements, their valences, and their amounts change. 4H + O2 => 2H2O is a chemical change because the valences change from unfilled to shared. Physical changes occur when the material phase changes. In fact, in 4H + O2 => 2H2O we also have a physical change...from gas to liquid water (in most cases). NOTE: That there was a chemical change here is incidental, the phase change is the physical change.
Phase changes are physical changes, not chemical changes. They involve a change in the state of matter (solid, liquid, gas) without altering the chemical composition of the substance.
Physical, as it remains water.
They're both physical changes. Phase changes are always physical changes. Chemical changes only involve chemical reactions - a change in the identity of the substance. That's why phase changes are physical changes. Ice cream remains ice cream when it melts.
its a phase change
Physical; all phase changes are physical changes because the composition does not change.
During a physical change the chemical molecule is not affected; physical changes are changes of phase or form.
It is a physical change. All phase changes are physical, not chemical. The chemical composition of water does not change when it changes from a liquid to a gas, or for that matter, to a solid.
Physical changes do not alter the chemical composition of a substance, only its physical appearance or state. Examples include changes in shape, size, phase (solid, liquid, gas), or state of matter (melting, freezing, dissolving).
its physical changes
See "Related Questions". Phase changes are reversible by adding or subtracting heat. In many cases chemical changes are not easily reversed.
When a liquid reaches boiling point it goes through a phase change, liquid to gas. Phase changes do not change the nature of a chemical so it is a physical change. This physical change can sometimes be caused by a chemical change though.
No, a typhoon is a physical structure energized by the latent heat of phase changes involving water.