Question

part ii: fill - ins. complete the sentence with the best term.

1. the ____ ____ of a substance is the point when the substance changes from the liquid state to the solid state.
2. the ______ of a substance is the point when the substance changes from the liquid state to the gas state.
3. ______ is a separation technique that involves pouring off one substance and leaving the other substance behind.
4. ______ is a separation technique that separates two liquids.
5. density describes the relationship between ____ and ____.

part iii: indicate whether the following is an example of an element, a compound or a mixture by checking the appropriate box. if the substance is a mixture, indicate whether it is a homogeneous or heterogeneous mixture. (1 point for each box correctly checked)

	element	compound	mixture	heterogeneous mixture	homogeneous mixture
2. copper
3. tossed salad
4. coffee with sugar
5. iron filings and rocks

Explanation:

1. Freezing point is the temperature at which a substance changes from liquid to solid.
2. Boiling point is the temperature at which a substance changes from liquid to gas.
3. Decantation is a separation technique where one substance is poured off, leaving another behind.
4. Distillation is a separation technique for two liquids (based on boiling points).
5. Density is mass per unit volume, so it describes the relationship between mass and volume.

For Part III:

• Carbon monoxide (\(CO\)) is a compound (two elements chemically combined).
• Copper (\(Cu\)) is an element (a pure substance with only one type of atom).
• Tossed salad has visible different components (heterogeneous mixture).
• Coffee with sugar has a uniform composition (homogeneous mixture).
• Iron filings and rocks have distinct, visible parts (heterogeneous mixture).

Answer:

1. freezing point
2. boiling point
3. decantation
4. distillation
5. mass; volume

Part III:

1. Compound
2. Element
3. Heterogeneous Mixture
4. Homogeneous Mixture
5. Heterogeneous Mixture