Chapter 1: Matter
Lesson 1.10: Practical: Investigating specific heat capacity Lesson overview OCR Specification reference Prac P5
Learning objectives • Use theories to develop a hypothesis. • Evaluate a method and suggest improvements. • Perform calculations to support conclusions. Learning outcomes • [O1] Use theories about specific heat capacity to write a hypothesis for the experiment. • [O2] Suggest improvements to the method for determining specific heat capacity. • [O3] Calculate, using the specific heat capacity equation, to justify a conclusion. Skills development • Use scientific theories and explanations to develop hypotheses. • Apply a knowledge of a range of techniques, instruments, apparatus and materials to select those appropriate to the experiment.
• Make and record observations and measurements using a range of apparatus and methods. • Evaluate methods and suggest possible improvements and further investigations. Maths focus • Substitute numerical values into algebraic equations using appropriate units for physical quantities. • Plot two variables from experimental or other data. • Determine the slope and intercept of a linear graph. Resources needed copper and aluminium blocks, each with two holes, 250 cm3 beaker, taps, thermometer, petroleum jelly, 50 W, 12 V heater, 12 V power supply, insulation, ammeter, voltmeter, leads, stopwatch, balance (mass); Worksheet 1.10, Practical sheet 1.10, Technician’s notes 1.10 Key vocabulary energy store, energy transfer, specific heat capacity
Teaching and learning Engage • Challenge students’ thinking and understanding of how to determine the specific heat capacity of a substance by discussion. Suggested questions to consider: What is specific heat capacity? What is the equation? What must be measured to experimentally determine the specific heat capacity of a substance? [O1, O2]
• Explain that the class will be doing an experiment to determine the specific heat capacity of three different substances. Have pairs of students discuss what is meant by ‘a hypothesis’ and what it should contain and then have them share their ideas with the class. [O1]
Challenge and develop • Students, either individually or in small groups, write a hypothesis on the specific heat capacities of copper, aluminium and water. Choose three groups to share their hypotheses with the class and let the others comment on what was good in that hypothesis and how it could be improved. This should be used for all students, to improve their own hypotheses. It might be wise to have small samples of the three materials to hand, so that the students can hold them (certainly the metals) to help them formulate their hypotheses. [O1]
OCR Gateway GCSE Physics: Teacher Pack
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