Chemical Reactions: Matter and Energy-(Damanjit Puri) by Damanjit Puri

6 min.: QUIZ/EXIT TICKET

dpuri4 — 2024-10-28 16:16:45 UTC

Administer a quiz with 6 multiple-choice questions to assess students' understanding of today's lesson.

Learning Objectives

dpuri4 — 2024-10-28 16:16:45 UTC

The student will be able to explain the difference between a physical change (no new substance) and a chemical change (new substance is formed).
The student will be able to identify real-life examples of exothermic processes (heat released) and endothermic processes (heat absorbed).
The student will be able to classify a change as physical or chemical and as exothermic or endothermic by using observations such as temperature change, color change, or new substance formation.

Group Discussion/5 min.

dpuri4 — 2024-10-28 16:16:45 UTC

Prompt students to summarize what they learned about physical and chemical changes, as well as exothermic and endothermic reactions. Encourage them to share any examples they observed or performed in class. Discuss as a class the key concepts of energy transfer and how changes in matter can release or absorb heat.

Essential Question: Type your answers here:

dpuri4 — 2024-10-28 16:16:45 UTC

How does the burning of wood demonstrate energy transformation in chemical reactions? Is it Exothermic or Endothermic Reaction? Why?

Extra Activity: ONLY IF TIME PERMITS

dpuri4 — 2024-10-28 16:16:45 UTC

OR TRY THIS: https://wordwall.net/resource/6635986/exothermic-and-endothermic-reactions

3 min video then 3 min quick experiment

dpuri4 — 2024-10-28 16:16:45 UTC

Watch this quick 3 min. video and write one thing in your science notebooks you noticed in this lesson.

Direct Instructions: Video:

dpuri4 — 2024-10-28 16:16:45 UTC

Exothermic Reactions (Release Heat)

Heat energy comes out of the reaction.
The surroundings feel warmer.
Examples:
- Burning a candle

Endothermic Reactions (Absorb Heat)

Heat energy goes into the reaction.
The surroundings feel cooler.
Examples:
- Ice melting
  💡 Tip for students:
  - Exo = Exit → heat leaves → warm
  - Endo = Enter → heat enters → cold

Guided Practice : A quick Science Experiment

dpuri4 — 2024-10-28 16:16:45 UTC

Guided Practice: Observe heat Energy during rubbing your hands:

Materials:

Your hands

Procedure:

Observe: Rub your hands together quickly for about 30 seconds.
Feel: Notice how your hands feel after rubbing them together.
Think: Is it an endothermic or Exothermic reaction? Why?

Discussion:

What happened when you rubbed your hands together?
Why did your hands feel warmer?
What kind of energy was transformed into heat energy?

5 min. Bell Ringer Activity & 5 min.Class Discussions

dpuri4 — 2024-10-28 16:16:45 UTC

Is ripping paper into small pieces a physical or a chemical change? Why? How can you tell if a change is physical or chemical? Give an example.

Paper Group Activity for Students.

dpuri4 — 2025-09-04 13:36:53 UTC