Unit 6 Matter as Particles

Topic

Factors influencing air pressure

Curriculum Link

6.6 Thermal Expansion and Contraction

Estimated Lesson Time

80 minutes

Introduction

In terms of particle theory, there are two factors influencing air pressure inside a container. They are the energy of air particles and the number of particles. This activity, consisted of 4 learning tasks, is to develop in students' skills to explain air pressure using particle theory. Students are engaged to effect of air pressure by observing the water level inside a straw in Task 1. Then students are guided to explain air pressure using particle theory in Task 2 and Task 3. Finally, students are invited to use the theory to make prediction regarding air pressure.

Key Question

What are the factors influencing air pressure?

Learning Objectives

In this activity, the students should be able to

  1. understand that the existence of air will exert pressure on the surroundings;
  2. use particle theory to explain daily life examples;
  3. visualize the micro-world with graphical representation (SP6);
  4. know the factors influencing air pressure in terms of particle theory.

Teaching Plan

Task (Time) Brief Description Materials Objectives

Engagement & Explanation
(15 min)

By comparing the water levels between two cases, students are aware of the existence of air and its effect on the surroundings. Students will be guided to explain in causal way.

 (1)

Exploration &
Explanation
(25 min)

Teacher provides students opportunity to explore ideas to explain why balloon expands by putting the bottle in hot water. In additional, students are required to explain the phenomenon using particle theory. In order to visualize the micro-world, graphical representation will be used.

(1), (2) & (3)

Elaboration & Explanation
(20 min)

Students apply the knowledge of gas pressure to solve some problems. Apart from this, they are required to use particle theory to explain the formation of gas pressure.

Ref videos:

Thus, two factors influencing air pressure are introduced and they are: energy gained by air particles and number of air particles.

 (2), (3) & (4)

Elaboration
(15 min)

Students are invited to make prediction and explain their predictions using particle theory.

 (2), (3) & (4)

*Apparatus and materials required: