Chapter 1: Matter
• High demand: Students should discuss why and how the specific heat capacity for glass should also be taken into account.
Explain • Ask students to draw (perhaps on mini whiteboards) an explanation for the difference in values of the two materials, based on ‘particles’ and stressing what they have previously learned about density. [O3]
• Students should sketch, using Worksheet 1.7, how they can represent particle models with arrows to show the direction of heat transfer for one of the systems investigated in the practical. [O2]
Consolidate and apply • Project images of different materials. Students can explore the materials and justify why materials are chosen for different purposes based on high or low specific heat capacity, for example, saucepan handles, saucepans, water jackets. [O1]
• Students should answer questions 1–8 on pages 26 and 27 of the Student Book. [O2] Extend Ask students able to progress further to clarify why gases have very high specific heat capacities and why the value for each gas is determined for constant volume and constant pressure.
Plenary suggestions Melt a small amount of ice over a Bunsen burner and ask students to predict, after two minutes of thinking and discussing in pairs, which of melting, boiling and evaporating happens at the quickest rate.
Answers to questions Worksheet 1.7
1.
9,425 J
2.
Copper (as it has the lowest specific heat capacity
3.
Energy for water = 66,880J Energy for copper = 6,240 J Energy for glass = 13,440 J
4.
Energy for the copper = 5,800 J; Energy for the water = 125,400 J therefore total energy = 131,200 J (131.2 kJ)
OCR Gateway GCSE Physics: Teacher Pack
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