Question

identify each mixture as either homogeneous or heterogeneous.

1. stainless steel
2. granite
3. air
4. blood
5. oil and water
6. wild bird seed
7. chunky peanut butter
8. vinegar (5% acetic acid)
9. gasoline

elements and compounds
circle the letter of the choice that best completes the statement or answers the question.

1. a substance that cannot be separated into similar substances by physical or chemical means in a(n)

a. compound. b. mixture. c. element. d. period.

1. a chemical combination of two or more different elements is a(n)

a. solution. b. compound. c. element. d. period.

1. the melting of a metal, like iron is an example of an _____

a. endothermic change b. exothermic change c. no change in energy

1. which of the following is an example of a compound?

a. gold b. silver c. aspirin d. copper

1. what are the horizontal rows in the periodic table called?

a. block elements b. groups or families c. grids d. periods

1. what are the vertical columns in the periodic table called?

a. block elements b. groups or families c. grids d. periods
label each substance as either an element or compound.

1. silicon
2. sodium chloride (table salt)
3. francium
4. nickel
5. hydrogen perox
6. co₂

write the symbol for each element. use the periodic table if you need help.

1. neon
2. calcium
3. iron
4. titanium
5. fluorine
6. sodium

Explanation:

Step1: Recall definitions

A homogeneous mixture has uniform composition throughout, while a heterogeneous mixture has non - uniform composition.

Step2: Analyze 35. stainless steel

Stainless steel is a solid solution, so it is homogeneous.

Step3: Analyze 36. granite

Granite has visible different components, so it is heterogeneous.

Step4: Analyze 37. air

Air is a gaseous mixture with uniform composition, so it is homogeneous.

Step5: Analyze 38. blood

Blood has cells suspended in plasma, so it is heterogeneous.

Step6: Analyze 39. oil and water

Oil and water do not mix uniformly, so it is heterogeneous.

Step7: Analyze 40. wild bird seed

Wild bird seed is a mixture of different seeds, so it is heterogeneous.

Step8: Analyze 41. chunky peanut butter

Chunky peanut butter has visible chunks, so it is heterogeneous.

Step9: Analyze 42. vinegar (5% acetic acid)

Vinegar is a liquid solution, so it is homogeneous.

Step10: Analyze 43. gasoline

Gasoline is a liquid mixture with uniform composition, so it is homogeneous.

Step11: Answer multiple - choice 44

An element cannot be separated into similar substances by physical or chemical means, so the answer is c.

Step12: Answer multiple - choice 45

A chemical combination of two or more different elements is a compound, so the answer is b.

Step13: Answer multiple - choice 46

Melting a metal like iron requires heat input, so it is an endothermic change, answer is a.

Step14: Answer multiple - choice 47

Aspirin is a compound, while gold, silver and copper are elements, so the answer is c.

Step15: Answer multiple - choice 48

Horizontal rows in the periodic table are called periods, so the answer is d.

Step16: Answer multiple - choice 49

Vertical columns in the periodic table are called groups or families, so the answer is b.

Step17: Label substances 1 - 6

1. silicon is an element.
2. sodium chloride is a compound.
3. francium is an element.
4. nickel is an element.
5. hydrogen peroxide is a compound.
6. CO₂ is a compound.

Step18: Write symbols 7 - 12

1. Ne
2. Ca
3. Fe
4. Ti
5. F
6. Na

Answer:

1. homogeneous
2. heterogeneous
3. homogeneous
4. heterogeneous
5. heterogeneous
6. heterogeneous
7. heterogeneous
8. homogeneous
9. homogeneous
10. c. element
11. b. compound
12. a. endothermic change
13. c. aspirin
14. d. periods
15. b. groups or families
16. element
17. compound
18. element
19. element
20. compound
21. compound
22. Ne
23. Ca
24. Fe
25. Ti
26. F
27. Na