Question

Is the process of changing from one phase of matter to another a physical change or a chemical change? Explain why

Answer 1

When molecules move from one phase to another they are still the same substance. There is water vapor above a pot of boiling water. Even though the physical state changed, the chemical properties were the same. On the other hand, a chemical change would build or break the chemical bonds in the H2O molecules

Answer 2

When molecules move from one phase to another they are still the same substance. There is water vapor above a pot of boiling water. ... Even though the physical state changed, the chemical properties were the same. On the other hand, a chemical change would build or break the chemical bonds in the water (H2O) molecules.