Question

physical science review: matter and change
physical vs. chemical properties and changes
a physical property is observed with the senses and can be determined without destroying the
object. for example, color, shape, mass, length, and odor are all examples of physical properties.
a chemical property indicates how a substance reacts with something else. the original
substance is fundamentally changes in observing a chemical property. for example, the ability of
iron to rust is a chemical property. the iron has reacted with oxygen, and the original iron metal
is changed. it now exists as iron oxide, a different substance.
identify the following as chemical (c) or physical (p) properties.

1. ____ blue color 8. ____ melting point
2. ____ density 9. ____ reacts with water
3. ____ flammability (burns) 10. ____ hardness
4. ____ solubility (dissolves) 11. ____ boiling point
5. ____ reacts with acid 12. ____ luster
6. ____ supports combustion 13. ____ odor
7. ____ sour taste 14. ____ reacts with air

in a physical change, the original substance still exists, it has only changed in form. in a
chemical change, a new substance is produced. energy changes always accompany chemical
changes.
identify the following as chemical (c) or physical (p) changes.

1. ____ salt dissolves in water 23. ____ milk sours
2. ____ silver tarnishes 24. ____ sugar dissolves in water
3. ____ an apple is cut 25. ____ wood rots
4. ____ liquid water changes to steam 26. ____ pancakes cook
5. ____ baking soda reacts with vinegar 27. ____ grass grows
6. ____ iron rusts 28. ____ a tire is inflated
7. ____ alcohol evaporates 29. ____ food is digested
8. ____ ice melts 30. ____ paper towel absorbs water

Explanation:

Physical properties are observable without altering the substance's identity; chemical properties involve reactivity that changes the substance. Physical changes alter form but not substance identity; chemical changes create new substances.

Answer:

Properties (C = Chemical, P = Physical)

1. P blue color
2. P density
3. C flammability (burns)
4. P solubility (dissolves)
5. C reacts with acid
6. C supports combustion
7. P sour taste
8. P melting point
9. C reacts with water
10. P hardness
11. P boiling point
12. P luster
13. P odor
14. C reacts with air

Changes (C = Chemical, P = Physical)

1. P salt dissolves in water
2. C silver tarnishes
3. P an apple is cut
4. P liquid water changes to steam
5. C baking soda reacts with vinegar
6. C iron rusts
7. P alcohol evaporates
8. P ice melts
9. C milk sours
10. P sugar dissolves in water
11. C wood rots
12. C pancakes cook
13. C grass grows
14. P a tire is inflated
15. C food is digested
16. P paper towel absorbs water