Question

chemistry matter review practice
name: blank

1. match each diagram with its correct description. diagrams will be used once. note: each circle represents an atom. if two atoms are touching, then they are bonded together and are a compound.

diagrams labeled a, b, c, d, e
__1. pure element – only one type of atom present.
__2. mixture of two elements – two types of uncombined atoms present.
__3. pure compound – only one type of compound present.
__4. mixture of two compounds – two types of compounds present.
__5. mixture of a compound and an element.

1. read each description and determine whether it is a pure substance or mixture. then further classify the matter (element, compound, homogeneous mixture, heterogeneous mixture).

table with columns: description, pure substance or mixture?, classification?

1. chocolate syrup is added to milk and stirred | mixture | homogenous mixture (solution)
2. copper metal (used to make wires) | pure substance | element
3. sand is added to water | mixture | heterogeneous
4. distilled water | element | compound (handwritten)
5. tap water | pure substance | homogeneous (handwritten)
6. helium gas (used to inflate a balloon) | blank | blank
7. table sugar | blank | blank
8. table sugar added to a cup of coffee and stirred | blank | blank
9. the air we breathe | blank | blank

Explanation:

Part 1: Matching Diagrams (Explanations for each match)

1. Pure Element (only one type of atom): Diagram C has only one type of atom (all circles are the same), so match with C.
2. Mixture of two elements (two uncombined atoms): Diagram E has two different uncombined atoms (black and white circles not bonded), so match with E.
3. Pure compound (only one compound): Diagram D has only one type of bonded atoms (same compound), so match with D.
4. Mixture of two compounds: Diagram A has two different bonded compounds (different molecule structures), so match with A.
5. Mixture of compound and element: Diagram B has a compound (bonded atoms) and an element (unbonded same - type atoms), so match with B.

Part 2: Classifying Matter (Correcting and Completing the Table)

Description	Pure Substance or Mixture?	Classification?
2. Copper metal	Pure Substance	Element (Cu is an element)
3. Sand + water	Mixture	Heterogeneous mixture (sand doesn’t dissolve, visible particles)
4. Distilled water	Pure Substance	Compound (H₂O, made of two elements)
5. Tap water	Mixture	Homogeneous mixture (contains dissolved minerals, uniform)
6. Helium gas	Pure Substance	Element (He is an element)
7. Table sugar	Pure Substance	Compound (C₁₂H₂₂O₁₁, made of elements)
8. Table sugar + coffee (stirred)	Mixture	Homogeneous mixture (solution, sugar dissolves)
9. Air we breathe	Mixture	Homogeneous mixture (gases like O₂, N₂, uniform)

Final Answers (Key Classifications)

• Part 1 Matches: 1. C, 2. E, 3. D, 4. A, 5. B
• Part 2 Table (corrected/completed as above)

Answer:

Part 1: Matching Diagrams (Explanations for each match)

1. Pure Element (only one type of atom): Diagram C has only one type of atom (all circles are the same), so match with C.
2. Mixture of two elements (two uncombined atoms): Diagram E has two different uncombined atoms (black and white circles not bonded), so match with E.
3. Pure compound (only one compound): Diagram D has only one type of bonded atoms (same compound), so match with D.
4. Mixture of two compounds: Diagram A has two different bonded compounds (different molecule structures), so match with A.
5. Mixture of compound and element: Diagram B has a compound (bonded atoms) and an element (unbonded same - type atoms), so match with B.

Part 2: Classifying Matter (Correcting and Completing the Table)

Description	Pure Substance or Mixture?	Classification?
2. Copper metal	Pure Substance	Element (Cu is an element)
3. Sand + water	Mixture	Heterogeneous mixture (sand doesn’t dissolve, visible particles)
4. Distilled water	Pure Substance	Compound (H₂O, made of two elements)
5. Tap water	Mixture	Homogeneous mixture (contains dissolved minerals, uniform)
6. Helium gas	Pure Substance	Element (He is an element)
7. Table sugar	Pure Substance	Compound (C₁₂H₂₂O₁₁, made of elements)
8. Table sugar + coffee (stirred)	Mixture	Homogeneous mixture (solution, sugar dissolves)
9. Air we breathe	Mixture	Homogeneous mixture (gases like O₂, N₂, uniform)

Final Answers (Key Classifications)

• Part 1 Matches: 1. C, 2. E, 3. D, 4. A, 5. B
• Part 2 Table (corrected/completed as above)