Question

understanding main ideas
identify each property as either physical or chemical. tell whether each physical property is extensive or intensive.

1. color
2. tendency to rust
3. boiling point
4. density
5. mass
6. ability to burn
7. malleability
8. ability to conduct electricity

match each term in column a with its example in column b.
column a

1. alloy
2. element
3. compound
4. vapor

column b
a. gold
b. table salt
c. steam
d. sterling silver (silver and copper)
understanding main ideas
identify each change as either physical or chemical.

1. breaking a pencil in half
2. wood burning
3. silver tarnishing
4. ice melting
5. hard - boiling an egg
6. grinding coffee beans
7. burning gasoline

identify the technique you would use to separate each mixture.

1. two substances with different boiling points

Explanation:

Step1: Recall property definitions

Physical properties can be observed without changing the substance's chemical identity. Chemical properties involve a change in the substance's chemical identity. Extensive properties depend on the amount of substance, and intensive properties do not.

Step2: Analyze each property

1. Color is a physical property and intensive (does not depend on amount).
2. Tendency to rust is a chemical property (involves iron reacting with oxygen).
3. Boiling point is a physical property and intensive.
4. Density is a physical property and intensive.
5. Mass is a physical property and extensive.
6. Ability to burn is a chemical property.
7. Malleability is a physical property and intensive.
8. Ability to conduct electricity is a physical property and intensive.

Step3: Match terms

1. Alloy - d. sterling silver (silver and copper) (an alloy is a mixture of metals).
2. Element - a. gold (an element is a pure substance made of one type of atom).
3. Compound - b. table salt (a compound is made of different elements chemically combined).
4. Vapor - c. steam (vapor is the gaseous state of a substance).

Step4: Identify change types

1. Breaking a pencil in half is a physical change (no new substance formed).
2. Wood burning is a chemical change (new substances like carbon - dioxide are formed).
3. Silver tarnishing is a chemical change (silver reacts with sulfur - containing compounds).
4. Ice melting is a physical change (change of state, no new substance).
5. Hard - boiling an egg is a chemical change (protein structure in egg changes).
6. Grinding coffee beans is a physical change (no new substance).
7. Burning gasoline is a chemical change (produces carbon - dioxide and water).

Step5: Separation technique

1. For two substances with different boiling points, distillation is used.

Answer:

1. Physical, Intensive
2. Chemical
3. Physical, Intensive
4. Physical, Intensive
5. Physical, Extensive
6. Chemical
7. Physical, Intensive
8. Physical, Intensive
9. d. sterling silver (silver and copper)
10. a. gold
11. b. table salt
12. c. steam
13. Physical
14. Chemical
15. Chemical
16. Physical
17. Chemical
18. Physical
19. Chemical
20. Distillation