Understanding the nature of elements, compounds and mixtures in Is Matter Pure – Class 9 Science Experiment

Chapter Name: Is Matter Pure

Activity Name: Understanding the nature of elements, compounds and mixtures in Is Matter Pure

Activity Description:

In this experiment, students will explore the properties of iron fillings and sulphur powder and investigate the nature of elements, compounds, and mixtures. The class will be divided into two groups, and each group will receive 5g of iron fillings and 3g of sulphur powder in a china dish.

Required Items:

• 5g of iron fillings
• 3g of sulphur powder
• China dishes
• Magnets
• Heat source (Bunsen burner or gas stove)
• Carbon disulphide
• Dilute sulphuric acid
• Dilute hydrochloric acid
• Lab setup (optional)

Step by Step Procedure:

1. Divide the class into two groups and distribute 5g of iron fillings and 3g of sulphur powder to each group in separate china dishes.
2. Activity for Group-1: a. Mix and crush the iron fillings and sulphur powder together. b. Use a magnet to check if the material obtained is attracted to the magnet.
3. Activity for Group-2: a. Mix and crush the iron fillings and sulphur powder together. b. Heat the mixture strongly until it becomes red hot. c. Remove the mixture from the flame and let it cool down. d. Use a magnet to check if the material obtained is attracted to the magnet.
4. Compare the texture and color of the materials obtained by the two groups.

If there’s a lab setup available: 5. Each group should divide the material obtained into two parts.

6. Add carbon disulphide to one part of the material, stir well, and filter the mixture.
7. Add dilute sulphuric acid or dilute hydrochloric acid to the other part of the material.
8. Repeat the same reactions separately with pure sulphur and pure iron.
9. Observe and record any changes that occur during these reactions.

Experiment Observations:

• Group-1 material (unheated mixture) might show some magnetism, depending on the degree of mixing and distribution of iron fillings.
• Group-2 material (heated mixture) might not show significant magnetism after heating and cooling.
• The texture and color of the two materials might differ, with Group-2 material potentially appearing more homogeneous.

Precautions:

• Handle iron fillings and sulphur powder with care, as they may cause skin irritation or eye discomfort. Wear appropriate safety gear, such as gloves and safety goggles.
• Use a heat source cautiously, and be mindful of the hot china dishes during and after heating.
• Avoid inhaling fumes or gases produced during heating.
• When handling chemicals like carbon disulphide and acids, follow proper safety protocols and work in a well-ventilated area.

Lesson Learnt from Experiment:

Through this experiment, students will learn about the properties of elements, compounds, and mixtures. The magnetism exhibited by Group-1 material indicates a mixture of iron and sulphur, while the lack of significant magnetism in Group-2 material suggests that heating and cooling the mixture might have led to the formation of a compound.

By performing additional reactions with the obtained materials and pure iron and sulphur, students will gain insights into the chemical changes that occur during these processes.