Question

physical and chemical properties and changes
name key
physical property

1. observed with senses
2. determined without destroying matter

chemical property

1. indicates how a substance reacts with something else
2. matter will be changed into a new substance after the reaction

identify the following as a chemical (c) or physical property (p):

1. blue color
2. density
3. flammability (burns)
4. solubility (dissolves)
5. reacts with acid
6. supports combustion
7. sour taste
8. melting point
9. reacts with water
10. hardness
11. boiling point
12. luster (shiny not shiny)
13. odor
14. reacts with air

physical change

1. a change in size, shape, or state
2. no new substance is formed

chemical change

1. a change in the physical and chemical properties
2. a new substance is formed

identify the following as physical (p) or chemical (c) changes.

1. nacl (table salt) dissolves in water.
2. ag (silver) tarnishes.
3. an apple is cut.
4. heat changes h₂o to steam.
5. baking soda reacts to vinger.
6. fe (iron) rusts.
7. alcohol evaporates.
8. ice melts.
9. milk sours.
10. sugar dissolves in water.
11. wood rots.
12. pancakes cook.
13. grass grows.
14. a tire is inflated.
15. food is digested.
16. paper towel absorbs water.

physical and chemical changes
part a
can you recognize the chemical and physical changes that happen all around us? if you change the way something looks, but haven’t made a new substance, a physical change (p) has occurred. if the substance has been changes into another substance, a chemical change (c) has occurred.

1. an ice cube is placed in the sun. later there is a puddle of water. later still the puddle is gone.
2. two chemical are mixed together and a gas is produce.
3. a bicycle changes color as it rusts.
4. a solid is crushed to a powder.
5. two substances are mixed and light is produced.
6. a piece of ice melts and reacts with sodium.
7. mixing salt and pepper.
8. chocolate syrup is dissolved in milk.
9. a marshmallow is toasted over a campfire.
10. a marshmallow is cut in half.

Explanation:

1. For physical and chemical properties:

• Physical properties are observed without changing the substance's chemical identity. Blue color, density, solubility, melting - point, hardness, boiling - point, luster, and odor are physical properties as they can be determined without a chemical reaction. Flammability, reacting with acid, supporting combustion, reacting with water, and reacting with air are chemical properties as they involve chemical reactions.

1. For physical and chemical changes:

• Physical changes do not result in a new substance. NaCl dissolving in water, an apple being cut, heat changing H₂O to steam, alcohol evaporating, ice melting, sugar dissolving in water, a tire being inflated, and a paper towel absorbing water are physical changes.
• Chemical changes result in a new substance. Silver tarnishing, baking soda reacting with vinegar, iron rusting, milk souring, wood rotting, pancakes cooking, grass growing, and food being digested are chemical changes.
• In Part A:
• Ice cube melting is a physical change. Mixing chemicals to produce a gas, bicycle rusting, two substances producing light, ice melting and reacting with sodium, toasting a marshmallow are chemical changes. Crushing a solid to powder, mixing salt and pepper, and dissolving chocolate syrup in milk are physical changes. Cutting a marshmallow in half is a physical change.

Answer:

Physical or Chemical Property

1. P
2. P
3. C
4. P
5. C
6. C
7. P
8. P
9. C
10. P
11. P
12. P
13. P
14. C

Physical or Chemical Change

1. P
2. C
3. C
4. P
5. C
6. C
7. P
8. P
9. C
10. P
11. C
12. C
13. C
14. P
15. C
16. P

Part A

1. P
2. C
3. C
4. P
5. C
6. C
7. P
8. P
9. C
10. P