Lesson Plan

• Describe the Celsius, Kelvin and Fahrenheit temperature scales and their reference points.
• Convert temperatures between Celsius, Kelvin and Fahrenheit using the correct formulas.
• Apply Kelvin temperatures in the ideal‑gas equation to calculate pressure, volume or amount of gas.
• Identify common mistakes when using the ideal‑gas law (incorrect temperature scale, wrong volume units, mismatched gas constant).

• Projector or interactive whiteboard
• Slide deck / printed handout on temperature scales and conversion formulas
• Worksheet with conversion and ideal‑gas problems
• Scientific calculators (or calculator apps)
• Video or model of a piston‑cylinder demonstration
• Exit‑ticket slips for the final check

Start with the question “What do you notice about a gas when its temperature increases?” to activate prior knowledge of kinetic theory. Review briefly how temperature is measured and why an absolute scale is needed for calculations. State the success criteria: students will convert temperatures accurately and use Kelvin in the ideal‑gas law.

1. Do‑now (5'): Quick conversion quiz – students change a set of temperatures between °C, K and °F.
2. Direct instruction (10'): Review the three scales, reference points and the four conversion formulas with worked examples.
3. Guided practice (10'): Whole‑class solving of additional conversion problems from the worksheet.
4. Demonstration (8'): Show a piston‑cylinder video/model and discuss why only Kelvin works in the ideal‑gas equation.
5. Application activity (12'): In pairs, calculate the pressure of a given amount of gas using the ideal‑gas law, converting temperature to K and volume to m³.
6. Check for understanding (5'): Exit ticket – write the Kelvin temperature required for a stated scenario and note one common mistake to avoid.

Recap the key points: temperature scales, conversion steps, and the necessity of Kelvin for the ideal‑gas law. Collect the exit tickets to gauge understanding, and assign a short homework task to convert a set of temperatures and solve an additional ideal‑gas problem.