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LEVE
Name:
Class:
Unit 11
Date:
NOTES
THERMAL PROPETIES OF MATTER
O-LEVELS REQUIREMENT
Candidates should be able to:
Sub-topic
1.
describe a rise in temperature of a body in terms of an increase in its internal energy (random
thermal energy)
9.1C
2.
define the terms heat capacity and specific heat capacity
11.1
3.
recall and apply the relationship thermal energy = mass x specific heat capacity x change in
temperature to new situations or to solve related problems
11.1
4.
describe melting/solidification and boiling/condensation as processes of energy transfer
without a change in temperature
11.2
5.
explain the difference between boiling and evaporation
11.4
6.
define the terms latent heat and specific latent heat
11.3
7.
recall and apply the relationship thermal energy = mass x specific latent heat to new
situations or to solve related problems
11.3
8.
explain latent heat in terms of molecular behaviour
11.3
9.
sketch and interpret a cooling curve
11.3
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Content neatly organised so
that students can do mental
compartmentalisation easily
NOTES CONTENT AND ORGANISATION
Sub-topic
Components
11.1
Heat Capacity
(A) Heat Capacity
(B) Specific Heat Capacity
11.2
Change of States of Matter
(C) Melting and Boiling
(D) Freezing (Solidification) and Condensation
11.3
Latent Heat
(E) Latent Heat of Fusion
(F) Latent Heat of Vapourisation
11.4
Evaporation
(G) Explaining Evaporation in Terms of Particles
(H) The Cooling Effect of Evaporation
(I) Factors affecting the Rate of Evaporation
(J) Applications of Evaporation
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11.1 Heat Capacity
Internal Energy (Revisit)
INTERNAL ENERGY
Kinetic Energy
Potential Energy
Temperature
Inter-particle Spacing
(A) Heat Capacity

The heat capacity, C, of an object is the amount of energy Q, required to raise the temperature of
an object by 1 oC or 1 K.
where
Q = thermal energy absorbed or given out (J)
C = heat capacity (JK-1 or J oC-1 )
 = change in temperature (K or oC)
*Note that 1 Degree Celsius = 1 Kelvin
SI Unit: Joules per Kelvin (…………………..….…….)
Other common Unit: Joules per Degree Celsius (…………………..….…….)
Example 1
John heats up a beaker of pure water. What is the heat capacity of this sample of water if 1260 J of
thermal energy is required to raise its temperature by 3 oC?
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(B)Specific Heat Capacity

The specific heat capacity, c, of an object is the amount of thermal energy, Q, required to raise the
temperature of a unit mass of an object by 1 oC or 1 K.
Where
c = specific heat capacity (Jkg-1K-1 or Jkg-1 oC-1)
C = heat capacity (JK-1 or J oC-1)
Q = thermal energy absorbed or given out (J)
m = mass (kg)
 = change in temperature (K or oC)
SI Unit: Joules per Kilogram per Kelvin (…………………..….…….)
Other common Unit: Joules per Kilogram per degree Celsius (…………………..….…….)
Example 2
When 211.2 J of thermal energy is transferred to a 12 g sample of pure aluminium, the temperature
rises from 15 o C to 35 oC. Calculate the specific heat capacity of aluminium.
By rearranging the terms, we have the following useful expression for thermal energy:
Example 3
What is the amount of thermal energy required to raise the temperature of a 2 kg mass of copper from
403 K to 453 K? Given that specific heat capacity of copper is 400 Jkg-1K-1.
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Example 4
(Transfer of Thermal Energy from one body to another, resulting in Thermal Equilibrium)
A copper block of mass 400 g is heated using a Bunsen burner. It is then transferred into 200 g of
water initially at 30 oC. The final temperature of the mixture is 50 oC. What is the initial temperature of
the copper block? Given specific heat capacity of copper is 390 Jkg-1K-1; water is 4200 Jkg-1k-1.
Questions that involved
Common Physics Situations
are labelled for students’ easy
consolidation.
Example 5
(Transfer of Thermal Energy from one body to another, resulting in Thermal Equilibrium)
A 50 J s-1 immersion heater is used to heat a beaker containing 300 g of ethanol. The mass of the
beaker is 60 g and the initial temperature of the ethanol is 30 C. What is the final temperature of the
ethanol after the immersion heater has been kept switched on for 10 minutes? Given specific heat
capacity of ethanol is 2500 Jkg-1K-1; glass is 650 Jkg-1K-1.
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Exercise Questions
1.
The heat capacity of a piece of copper is 200 J °C -1. What is the amount of thermal energy
required to raise its temperature from 30 °C to 100 °C?
Exercise Questions (Basic and Intermediate) after every
1-2 concepts taught
2.
When a piece of iron is cooled from 70 °C to 40 °C, the heat given out is 690 J.
(a) What is the heat capacity of the piece of iron?
(b) Given that the mass of the iron is 50 g, calculate the specific heat capacity.
3.
What is the amount of thermal energy required to raise the temperature of 2 kg of copper from
230 K to 280 K given that the specific heat capacity of copper is 400 J kg-1K-1?
4.
0.5 kg of orange juice at 30 °C is placed in a refrigerator which can remove heat at an average
rate of 20 Js-1. How long will it take to cool the orange juice to
5 °C ? (Assume that the specific heat capacity of orange juice is 4200 J kg-1 °C -1)
Only Section 11.1 - Heat Capacity is shown in this sample
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