🔬 Part 1: Understanding the Basics

1. Define a pure substance in your own words:

2. Define a mixture in your own words:

3. What is the main difference between pure substances and mixtures?

Pure substances can be separated physically, mixtures cannot

Pure substances contain only one type of particle, mixtures contain multiple types

Pure substances are always liquids, mixtures are always solids

There is no difference between them

🏷️ Part 2: Classification Challenge

4. Classify each of the following as either a pure substance (P) or mixture (M). Write P or M in the space provided:

a) Table salt (sodium chloride) ____

b) Tap water ____

c) Pure gold ____

d) Fruit salad ____

e) Sugar (sucrose) ____

f) Air ____

g) Distilled water ____

h) Chocolate chip biscuit ____

i) Pure iron ____

j) Soil ____

5. From your lunchbox today, identify two examples of mixtures and explain why they are mixtures:

⚛️ Part 3: Particle Theory Connection

6. Draw particle diagrams to show the difference between a pure substance and a mixture. Use circles to represent different types of particles:

Pure Substance:

Mixture:

7. Which of the following statements about particles in pure substances and mixtures are correct? (Check all that apply)

Pure substances contain identical particles throughout

Mixtures contain different types of particles

Particles in mixtures lose their individual properties

Pure substances have consistent properties throughout

Mixtures can be separated by physical methods

🔧 Part 4: Separation Methods

8. Match each mixture with an appropriate separation method:

1. Sand and water

2. Salt and water

3. Iron filings and sulfur

4. Oil and water

A. Using a magnet

B. Evaporation

C. Filtration

D. Separating funnel

9. Explain why physical separation methods work for mixtures but not for pure substances:

🌏 Part 5: Real-World Applications

10. Fill in the blanks using the words: pure substance, mixture, physically, chemically, properties

Sea water is a _____________ because it contains salt dissolved in water. The salt and water can be separated _____________ by evaporation. Pure gold is a _____________ because it contains only gold atoms and has consistent _____________ throughout. To break down a pure substance, you would need to separate it _____________.

11. A mining company has found a sample that contains both gold and sand. Describe two methods they could use to separate the gold from the sand:

12. Why is it important for scientists and industries to understand the difference between pure substances and mixtures?