Which of the following statements is/are correct regarding 'changes of state of matter'? (A) A change of state of matter is a physical change. (B) A change of state of matter is an irreversible change.

A change of state of matter is a physical change because it only alters the physical properties of the substance without changing its chemical composition. A change of state is generally a reversible change, not an irreversible one. You can undo the change by reversing the conditions, such as cooling steam back into liquid water or freezing water back into ice. Examples of a physical change are melting ice into water, boiling water, and water vapor changing to water. Examples of an irreversible change are wood burning, rusting of iron, souring of milk.