Question

practice: classification
part 1: classify the following as a substance (s) or a mixture (m)
__1. table salt (nacl) 2. trail mix __3. sugar
__4. copper 5. cereal __6. concrete

part 2: classify the following substances as elements (e) or compounds (c)
__7. mercury 8. water __9. carbon dioxide
__10. iron 11. aluminum __12. oxygen (o₂)

part 3: classify the following mixtures as homogeneous (ho) or heterogeneous (he)
__13. coffee 14. pizza __15. sand
__16. saltwater 17. bronze __18. milk
__19. paint 20. air __21. soil

part 4: classify the following as an element (e), compound (c), homogeneous mixture (ho) or heterogeneous mixture (he)
__22. calcium 23. hydrogen (h₂) __24. orange juice with pulp
__25. baking soda (nahco₃) 26. helium __27. limestone (caco₃)
__28. salad dressing __29. vinegar (ch₃cooh)

part 5: each of the following circles represents an atom. if two atoms are touching than they are bonded together. knowing this, classify each picture as one of the following:
a = element
b = compound
c = mixture of elements
d = mixture of compounds
e = mixture of elements and compounds

1. image 31. image 32. image
2. image 34. image 35. image

matter unit
© it’s not rocket science® 2017

Explanation:

Part 1: Substance/Classification

Step1: Define substance/mixture

Substances have fixed composition; mixtures are physical combinations.

1. Table salt (NaCl): S (pure compound)
2. Trail mix: M (physical mix of foods)
3. Sugar: S (pure compound)
4. Copper: S (pure element)
5. Cereal: M (physical mix of grains)
6. Concrete: M (physical mix of materials)

Part 2: Element/Compound

Step2: Define element/compound

Elements are single-type atoms; compounds have bonded atoms.

1. Mercury: E (single element)
2. Water: C ($H_2O$, bonded atoms)
3. Carbon dioxide: C ($CO_2$, bonded atoms)
4. Iron: E (single element)
5. Aluminum: E (single element)
6. Oxygen ($O_2$): E (same-element molecules)

Part 3: Homogeneous/Heterogeneous

Step3: Define mixture types

Homogeneous = uniform; Heterogeneous = non-uniform.

1. Coffee: HO (uniform composition)
2. Pizza: HE (distinct components)
3. Sand: HE (varying particle sizes/composition)
4. Saltwater: HO (uniform dissolved salt)
5. Bronze: HO (uniform alloy)
6. Milk: HO (uniform colloidal mixture)
7. Paint: HE (settles into distinct layers)
8. Air: HO (uniform gas mixture)
9. Soil: HE (distinct organic/inorganic parts)

Part 4: Full Classification

Step4: Apply all matter categories

Classify into element, compound, homo/hetero mixture.

1. Calcium: E (single element)
2. Hydrogen ($H_2$): E (same-element molecules)
3. Orange juice with pulp: HE (pulp is distinct)
4. Baking soda ($NaHCO_3$): C (bonded atoms)
5. Helium: E (single element)
6. Limestone ($CaCO_3$): C (bonded atoms)
7. Salad dressing: HE (separates into layers)
8. Vinegar ($CH_3COOH$ solution): HO (uniform acid-water mix)

Part 5: Particle Diagram Classification

Step5: Match diagrams to categories

Use definitions for elements, compounds, mixtures.

1. C (mixture of two different elements)
2. D (mixture of same compound molecules)
3. A (single type of element atoms)
4. A (single type of element molecules)
5. B (single type of compound molecules)
6. E (mixture of element atoms + compound molecules)

Answer:

Part 1

1. S
2. M
3. S
4. S
5. M
6. M

Part 2

1. E
2. C
3. C
4. E
5. E
6. E

Part 3

1. HO
2. HE
3. HE
4. HO
5. HO
6. HO
7. HE
8. HO
9. HE

Part 4

1. E
2. E
3. HE
4. C
5. E
6. C
7. HE
8. HO

Part 5

1. C
2. D
3. A
4. A
5. B
6. E