EVERYDAY SCIENCE

Detailed explanation-1: -(h) Rock is crushed into powder. Physical, it s still rock with the same chemical identity just divided into smaller particles.

Detailed explanation-2: -A physical change is any change that alters the form or appearance of a substance but does not change it into another substance: bending, crushing, and cutting. Changes in the state of matter: freezing, boiling, and melting are physical changes.

Detailed explanation-3: -Crushing of a chalk piece to get powdered chalk is an example of physical change.

Detailed explanation-4: -Conversion of chalk to chalk powder is a physical change as there is no chemical reaction involved in it. The physical state of the chalk remains the same (solid), and chalk powder can be converted back to chalk.

Detailed explanation-5: -It is a physical change because powdering means big size of sugar crystal is crushed into small pieces and ultimately into powder here the size only changes but not any structural change so it is a physical change not a chemical change.