Specific Heat Capacity Notes These areas have extra notes to help you. Make notes as we go along, always including these post-its

Objectives Objectives BRONZE SILVER GOLD Identify what we mean by ‘heating up’ and ‘cooling down’. SILVER Describe which materials heat and cool the quickest. GOLD Define specific heat capacity and use the relevant equation to calculate the value of ‘c’ for different materials.

It’s 1pm on the beach, why does the sand feel Engage Groups of four Discuss SEA Pick a leader Hints What energy is applied? How do they differ? Can we assume any control factor? It’s 1pm on the beach, why does the sand feel hotter than the sea? SAND

SPECIFIC HEAT CAPACITY Starter Explored Groups of four How much a substance’s temperature rises due to an energy input is related to a feature known as… SPECIFIC HEAT CAPACITY Why does the sand feel hotter than the sea? Discuss SAND SEA Pick a leader Is the energy applied the same? Well the mass of one is bigger…..assume it’s not! So if it’s not down to the mass…. Hints What energy is applied? How do they differ? Can we assume any control factor?

Explore Mass If a substance is being heated, what factors would affect how its temperature changes? Energy Input Substance! (SHC) Remember When we controlled the mass of the sand and water (and the energy in) the only thing that affected the temp was the substances themselves!

a.k.a the end temperature – the start temperature Explore ∆Q Change in energy m Mass SO….The specific heat capacity of an object (or substance) is the energy needed to raise the temperature of 1kg of that object by 1K! This must be WITHOUT a change in state ∆Q=mc ∆T ∆T Change in temperature Extension Work out the units for ‘c’! Task Write down the units for ΔQ, m and ΔT "∆T" ΔQ= J ΔT= K ( or ˚C) m= Kg When we use ∆T what we mean is ∆T2−∆T1 a.k.a the end temperature – the start temperature J= kg x ? x K So the value of ? must contain J and counteract K and Kg 3. So ‘c’ is measured in Jkg-1K-1

Progress Checker Identify Calculate the energy require to raise the temperature of 500 g of water from 20K to 100K (3 marks) Convert Rearrange Values of c Al: 900 Concrete: 850 Copper: 360 Lead: 130 Oil: 2100 Water: 4200

Progress Checker Identify Q: Calculate the energy require to raise the temperature of 5000 g of water from 20K to 100K (3 marks) A: 1) 2) m = 5kg, ∆T=80K,c= 4200 Jkg-1K-1 3) so… 5 x 80 x 4200= 1.7 x 106 J ∆Q=mc ∆T Convert Practice time: You have 15mins to work on the questions on the hand out. If you finish early, create a question of your own! Swap – Different Colour Pen- Peer Assess Rearrange Values of c Al: 900 Concrete: 850 Copper: 360 Lead: 130 Oil: 2100 Water: 4200

Theoretical Practical In pairs How can we measure the specific heat capacity of a liquid? Discuss Task 1: Identify what variables we would need to control and which ones we would measure Task 2: Suggest equipment that we could use. Go to another group and discover their ideas. Compare Task 3: Draw the diagram of the set up you would use. Compare it with the one shown to you Equation hints What equation would work out the energy in? Don’t forget you have to consider the energy is shared between the liquid AND the calirometer! Task 4: CHALLENGE: What would be the equation? Extension: rearrange to get ‘c’ of the liquid

Wider Context Exam Question Change in energy Explain how knowing the specific heat capacity of liquids and metals is useful for the design of the following objects 6 marks m Mass ∆T Change in temperature This solar panel is for heating water..

∆Q m ∆T Wider Context Exam Question Change in energy Explain how knowing the specific heat capacity of liquids and metals is useful for the design of the following objects 6 marks Definition of specific heat capacity Can calculate the energy needed to heat water to a certain temperature This helps to calibrate the shower Different metals will have different specific heat capacities In a solar panel, the energy from the sun is transferred to the water to heat it Allows you to calculate the time needed to change the temp of water for different metals Hence allows you to determine the optimum metals to construct the pipes used. Copper is the commonly used metal m Mass ∆T Change in temperature Peer assess Swap and mark Add missing information WWW EBI

Objectives Objectives BRONZE SILVER GOLD Red Identify what we mean by ‘heating up’ and ‘cooling down’. Amber SILVER Describe which materials heat and cool the quickest. Green Reflection GOLD Define specific heat capacity and use the relevant equation to calculate the value of ‘c’ for different materials. What energy is applied? How do they differ? Can we assume any control factor?

Objectives Independent Study Write half a page explaining how you would identify the specific heat capacity of a metal block Hints: Choose an example metal, what factors will you need to control and measure, what calculations would you do after?