Question

hapter 2 the nature of matter additional problems
sson 4 mixtures of matter
ssón practice

1. classify each of the following as either a heterogeneous or homogeneous mixture.

a. tap water
b. air
c. raisin muffin

1. compare mixtures and substances.
2. describe the separation technique that could be used to separate each of the following mixtu

a. two colorless liquids
b. a non - dissolving solid mixed with a liquid
c. red and blue marbles of same size and mass

1. design a concept map that summarizes the relationship between matter, elements, mixtures,

compounds, pure substances, homogeneous mixtures, and heterogeneous mixtures.

Explanation:

1. For classification: Homogeneous mixtures have uniform composition; heterogeneous have distinct visible components.
2. For comparison: Substances have fixed composition/unique properties; mixtures are variable combinations.
3. For separation techniques: Match method to mixture properties (boiling point, particle size, physical appearance).
4. For concept map: Organize from broad (matter) to specific categories with hierarchical connections.

Answer:

1.
a. tap water: Homogeneous mixture
b. air: Homogeneous mixture
c. raisin muffin: Heterogeneous mixture

2.

• Pure substances have a fixed, definite chemical composition and unique characteristic properties (cannot be separated into simpler substances by physical means; includes elements and compounds).
• Mixtures are physical combinations of two or more pure substances, with a variable composition; their properties depend on the proportions of the components, and they can be separated by physical methods.

3.
a. two colorless liquids: Distillation (if they have different boiling points) or chromatography
b. a non-dissolving solid mixed with a liquid: Filtration
c. red and blue marbles of same size and mass: Manual sorting (physical picking)

4.

Matter
├─ Pure Substances
│  ├─ Elements (cannot be broken down chemically)
│  └─ Compounds (made of 2+ elements, chemically combined)
└─ Mixtures
   ├─ Homogeneous Mixtures (uniform composition, e.g., solutions)
   └─ Heterogeneous Mixtures (non-uniform, distinct components)