Lesson 5: Charles' law and Gay-Lussac's law

Figure F.17 - Charles' law cartoon

Charles' law: V₁ = V₂

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Gay- Lussac's law: P₁ = P₂

_{T1 T2}

• Hook: Water will be boiled in front of the class, students will note what occurs. The class will discuss what is happening to liquid molecules (volume, energy) as it is boiled. Students should notice that the water molecules have more energy upon being heated, thus, the water will evaporate and become a gas.

• Action: Students will answer questions based on Charles’s Law and Gay-Lussac’s Law on the board. This provides students with proper practice before moving on to their homework. The first example can be done as a class, the second can be done by a student volunteer and the third will be done individually and the method and answer will be taken up. This follows the gradual release method.
• Debrief: Exit slip – “Using Charles’s Law and Gay-Lussac’s Law explain why it’s not a good idea to inflate car tires fully on a hot day. This question will be used to enforce the application part of this lesson where students can now bring the mathematical relationships they have just learned and apply it to a real life situation, something they may have been told before but never understood why.