Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
Appendix A
Lesson Procedures
1
QCP521
Due: 15/10/05
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
Time/min
i.
ii.
5
(5)
iii.
iv.
i.
7
(12)
ii.
Activities
Walk into class, lay cloth on teacher’s table and
take out a block of ice, a crushed icemaker and a
bowl. Get a student volunteer to make a bowl of
crushed ice.
QCP521
Due: 15/10/05
Resources
Block of ice,
crushed ice
maker, bowl
and cloth
While student is making crushed ice, announce Whiteboard,
the topic for today, melting, boiling and markers,
evaporation, by writing on the whiteboard and handouts
distribute the handout for today’s lesson.
Put a thermometer into the bowl of crushed ice Thermometer,
and ask a second volunteer, one with better timer
grades, to take the temperature down for every 5
minutes during the lesson. (See Appendix C)
PC/Laptop to be started and ready to be used for PC/Laptop
the later part of the class.
Recap on the kinetic model for matter with aid
of a pictorial representation given in notes.
Students will be given 3 minutes to discuss in
pairs with their neighbours, the properties of
solid, liquid and gas based on the picture and
knowledge learnt earlier (Activity 1). They are to
categorize their findings under
Handouts,
1. Arrangement of particles
OHP
2. Movement of particles
At the end 3 minutes, each pair will be asked one
property for either state of matter. There should
be enough materials to cover 18 pairs of students
at least. The answers would be summarized using
2
i.
Rationale
Activity to capture student’s attention and to
prepare for the melting ice experiment for the
class.
ii.
Introduce the topic that they will learn today.
iii.
To let students realize that ice melts at constant
temperature and use the data points in the melting
curve later. The volunteer may not be able to
concentrate on the lesson fully so he/she
preferably has to be smarter or has better grades.
iv.
The first 5 minutes is to setup and prepare the
lesson for class. Alternatively, the lesson could be
held in a lab with all materials ready for lesson.
Then the first 5 minutes is to wait for students to
arrive and settle down.
The kinetic model for matter can be used to
describe the phenomenon of change in states. So it
is a good time to let students recall what they had
learnt in the past and participate in the lesson
through discussions.
i.
ii.
This is also a good chance for students to warm-up
for the lesson and engages their minds into thinking.
Students are already exposed to model for matter so
minimal time will be spent on this area.
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
Time/min
i.
10
(22)
ii.
iii.
i.
10
(32)
ii.
iii.
Activities
OHP during the discussion and students have to
copy down notes on their handouts at the same
time.
Based on the kinetic model for matter, explain
melting, highlighting the fact that temperature
reminds constant for melting. Repeat the same for
freezing. Ask students to recall what
melting/freezing point is.
Use the whiteboard to illustrate the change of state
with drawings while explaining to emphasize the
fact that melting occurs without any change in
temperature is a result of breaking or forming of
bonds during change of state.
Resources
QCP521
Due: 15/10/05
Rationale
i.
Linking the model for matter to melting and
freezing in explanation is to help the students grasp
and remember the definitions. Such discussions
work best with audio learners.
ii.
Handouts,
OHP,
whiteboard
iii.
and markers
The whiteboard illustrations are helpful for visual
learners to remember the definition.
i.
Doing actual experiment with students provides a
better learning channel for visual and kinesthetic
learners as compared to just explaining the process.
The experiment also serves to strengthen what they
had learnt about melting earlier.
After discussion, definitions for melting and
freezing will be shown via OHP for students to
take down notes.
Introduce the melting curve by using the data
points collected by student volunteer since the
beginning of class. The bowl of crushed ice with
thermometer will be passed around the class for
everyone to see when the curve is plotted.
Bowl of
melting ice
with
Using a laptop with MS Excel, the melting curve
ii.
thermometer,
will be sketched together with the class on their
PC/Laptop
handouts. The template for the curve will be
and, handouts
prepared beforehand (Activity 2) (See Appendix D:
Excel template)
iii.
The curve will have to be labeled at strategic points
3
Finally, copying down notes are targeted to
kinesthetic learners
The use of IT helps in creating the sketch quickly
and accurately. It saves time and has the novelty
effect as students hardly draw graphs using
computers.
The use of questioning is to foster thinking among
students and at the same time make sure that they
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
Time/min
i.
10
(42)
ii.
10
(52)
i.
ii.
i.
12
(64)
Activities
according to the states of the matter present.
Explain that boiling and condensation are
transitions of states just like melting and freezing.
Give students 3 minutes to discuss in pairs how to
fill in the blanks in the handout regarding boiling
and condensation (Activity 3).
Ask individuals to share their answers with the
class while going through the solutions with OHP.
Introduce evaporation as another process for liquid
to change to vapour and compare it with boiling. A
video of boiling water will be shown continuously
for this segment while the bowl of melted ice used
previously will be used to demonstrate evaporation
process.
Students will be asked to pick out 6 differences
between boiling and evaporating by comparing the
video and the bowl of water. The differences will
be summarized with OHP for students to take note
of. For this segment, the OHP will be projecting
out of position to incorporate the video at the same
time (Activity 4).
Molecules of matters will be represented in the
form of marbles in container. Vibrating the
container of marbles will simulate the molecular
motion/vibration. Any marbles that escaped will be
considered as “evaporated”. The same set up will
be used to show how various factors can affect
evaporation process. These will be demonstrated
through a series of experiments – see Appendix C:
Resources
i.
OHP,
handouts
QCP521
Due: 15/10/05
Rationale
are alert and paying attention in class.
As boiling & condensation are processes very
similar to melting and freezing. The discussion
gives students a chance to synthesize both ideas
together.
ii.
This is a chance to gauge and see if students
understand the lesson on melting.
i.
Videos and the bowl of water will be able to capture
the student’s imagination better than just sketching
or showing a picture of boiling water. Using
multimedia approaches would also appeal to
different types of learners.
ii.
Posing the question to students and getting them to
participate by providing answers will ensure that
students are engaged in the lesson. They will also
have to go through the thinking processes to
compare the differences.
Handouts,
i.
OHP,
Marbles,
Styrofoam
balls,
containers,
small tank, a ii.
large bottle of
The model for matter is actually very useful in the
learning of topics in thermal physics. The
experiment here is to try to link the macroscopic
view – thermal physics, to the microscopic view –
individual atoms and molecules.
Handouts,
OHP, Video,
Laptop/PC
4
It is possible to incorporate inquiry-based learning
in the demonstration. Under level 2 of Herron's
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
Time/min
Activities
Resources
Demonstrations and Microteaching for more water.
information.
ii.
4
(68)
Rationale
Inquiry Level (where Higher order thinking such as
synthesis would be involved for that question.),
questions like: what is needed to be done to the
model if studies on how temperature affects
evaporation are to be carried out, may be posted to
the students.
Various conditions, such as size of marbles, would
be varied and students will be asked how the
condition relates to real liquid and predict the
outcome. The demonstration will be carried out
and discussion in the form of Q&A will be carried
out to summarize the facts. This will be repeated
for other conditions.
1. Students are to close all their textbooks and keep
all their notes for this short summary of the day’s
lesson. Students will be asked to spot the mistake
in the summary and correct them. They will have
to complete a simple concept map for this chapter
to round up the lesson. A sample of mixed ability
students will be quizzed.
OHP,
handouts
2. Announce the homework details (Workbook
Practice 9, due next lesson) and the topic for next
lesson. Clean up any mess and bring in National
Education by role modeling. Ask the students to
pick up litter and start keeping Singapore clean by
ensuring their classroom is clean.
QCP521
Due: 15/10/05
i.
This is to evaluate the progress of the students and
how much they manage to pick up from the 2
period lessons. If all students asked were able to
spot the mistake and provide answers, it will be an
indication that the students had gained the required
knowledge of the topic and had managed to
comprehend it.
ii.
To reinforce concepts learnt; provide link to next
topic and to bring in National Education by role
modeling.
The ‘lesson plan’ above is being set for 68 minutes of lesson with 2 minutes for allowance. Should the lesson end before time, additional thinking
questions (Appendix C) related to the demonstrations may be posted to the students.. On the other hand, it is possible to leave out one or two of the
blocks for the next lesson and go straight to round up the lesson in the event that the lesson is going too slowly. This is because most components
in the lesson are in blocks of about 10 minutes. As for the portion regarding microteaching, last part of the lesson could be roped in should the
microteaching component planned was completed earlier than expected.
5
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Appendix B
Handouts (Teacher’s Copy)
Handouts (Student’s Copy)
Note:
For the lesson, the teacher will be using
the student’s copy with either an OHP or
visualizer and fill in the blanks with
student’s correct answers in class. The
teacher’s copy will be for reference
purposes only. Both copies will be printed
in transparency.
7
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Melting, Boiling and Evaporation (Teacher’s Copy)
Solid
Liquid
Vapour
Arrangement
Arrangement
Arrangement
1.) Closely packed
1.) Loosely packed
1.) Very far apart
together
together (slightly further
2.) No pattern
2.) Regular pattern
apart)
3.) Low densities and
3.) High densities
2.) No pattern
highly compressible
4.) Fixed volume
3.) High densities
4.) No fixed volume
4.) Fixed volume
Movement
Movement
Movement
1.) Vibrate about fixed
1.) Free to move within
1.) High-speed random
position
container containing it
motion
2.) Strong intermolecular
2.) Takes shape of
2.) No fixed shape
bonds (fixed shape)
container
Activity 1: Discuss in pairs, the characteristics of solid, liquid and
vapour in terms of molecular arrangement and movement in
the table above. (3 minutes)
Be prepared to share your answers with the rest of the class.
8
Chia Guo Hao
054396H23
Melting:
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Melting is the change of state from solid to liquid without a change in
temperature.
Freezing:
Freezing is the change of state from liquid to solid without a change in
temperature.
Melting Point: The temperature point where solid melts and liquid freezes
Melting (Freezing) requires (releases) energy and the heat absorbed (given out) in the
process is called the latent heat of fusion. The energy will be used to break (form)
bonds for the matter.
Purely Solid
Melting Curve of Ice
A-B
30
Mixture of
Solid and
Liquid
25
20
Purely Liquid
o
Temperature ( C)
B-C
D
15
C-D
10
Mixture of
Liquid and
Vapour
5
D-E
B
0
0
-5
Purely
Vapour
C
5
10
15
20
25
30
E-F
A
Time (Minutes)
Time (min)
Temperature
(oC)
0
3
12
21
25
27
30
-5
0
0
0
5
10
19
Activity 2: From the data collected by your friends, quickly sketch a
melting curve in the space provided above and label the
graph according to the labels given on the right.
9
Chia Guo Hao
054396H23
Boiling:
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Boiling is the change of state from liquid to vapour without a change
in temperature.
Condensation: Condensation is the change of state from vapour to liquid without a
change in temperature
Boiling Point: The temperature point where liquid boils and vapour condenses
Boiling (Condensation) requires (releases) energy and the heat absorbed (given out) in
the process is called the latent heat of vaporization. The energy will be used to break
(form) bonds for the matter.
Purely Solid
Freezing Curve of Water
E-F
120 A
100
Mixture of
Solid and
Liquid
C
B
D-E
Purely Liquid
o
Temperature ( C)
80
60
C-D
40
Mixture of
Liquid and
Vapour
20
B-C
D
0
0
10
20
30
40
-20
Purely
Vapour
E
50
60
F
A-B
Time (Minutes)
Activity 3: Boiling/Condensation is similar to melting/freezing. Discuss
in pairs how would you complete the blanks above by
inferring from melting and freezing or otherwise. (3
minutes).
Be prepared to share you answers with the rest of the class.
10
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Evaporation: Evaporation is the change of state of a liquid into its vapour at any
temperature. Evaporation requires energy and heat is absorbed from the
surroundings and it occurs only at the exposed surface of the liquid
Activity 4: Watch the video of a pot of water boiling and compare it to a
bowl of water evaporating. Can you pick out differences
between boiling and evaporation to complete the figure and
table below? (3 minutes)
Be prepared to share your solutions with the class
Differences
Boiling
Evaporating
Different temperature
Steam observed for boiling only
Bubbles formed for boiling only
Bubbles observed within liquid
Presence/absence of heat source*
* Boiling can occur at absence of heat source. E.g. reducing pressure. But heat source is present here.
Comparing Boiling and Evaporation
Boiling
Evaporation
1. Occurs at fixed temperature 1. Occurs at any temperature
Temperature
2. Temperature
remains 2. Temperature may change
constant during boiling
3. Takes place within liquid
during evaporation
3. Takes
exposed
Occurrence
place
only
at
of
the
surface
liquid
Bubbles
Supply of Heat
Process
4. Bubbles are formed
4. Bubbles are not formed
5. Heat supplied by energy 5. Heat
source
supplied
by
surroundings
6. Liquid changes to vapour 6. Liquid changes to vapour
state quickly
state slowly
11
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Factors affecting rate of evaporation
Temperature
Humidity of
surrounding
Exposed surface
area of liquid
Raising the temperature of liquid increases rate of
evaporation as the liquid molecules are more energetic
Humidity is a measure of the amount of water vapour present
in the air. The higher the humidity, the more water vapour is
present in air and the evaporation rates become slower
The larger the exposed surface area of the liquid, the faster
the rate of evaporation will be since evaporation occurs only
at the exposed surface area
Movement of air
Moving air (wind) removes the molecules of liquid as soon
above surface of
as it escapes to become vapour thus increases the rate of
liquid
Pressure
evaporation
Lower atmospheric pressure increases the rate of evaporation
as it is easier for liquid molecules to escape
Different types of liquid have different properties that will
affect the rate of evaporation. For example, mercury hardly
Nature of liquid
evaporate at room temperature due to the high boiling point
while volatile liquid such as alcohol or ether evaporates
quickly
Modern Application of Evaporation
1. Coffee shop uses a fan that sprays mist of water droplets to cool down customers
and the surrounding during a hot day. When the water droplets evaporate, it
absorbs and takes away heat from the customers and the surroundings thus cooling
the area down.
2. Hair dryer makes use of hot air to blow dry our hair. The hot air increases the
temperature and the wind increases movement of air to increase the rate of
evaporation, hence it can dry our hair quickly.
3. In Singapore, we hang wet clothes on poles outside the HDB flat to dry them. The
sun will increase the temperature while wind increases movement of air to
increase the rate of evaporation. Finally, clothes are hanged in such a way that a
large surface area of the wet clothes is exposed to increase evaporation.
12
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Summary of Melting, Boiling and Evaporation
In this chapter, you learned that melting, freezing, boiling and condensation are
processes when matter changes from one state to another at a fixed temperature. The
temperature remains constant during these processes. You also learnt that heat energy
absorbed by the molecules during melting and boiling processes is used to break intermolecular bonds while heat energy is released by the molecules during freezing and
condensation when intermolecular bonds are being formed. The processes can be
observed through the temperature against time graph for cooling and heating of
matter.
Evaporation, though similar to boiling, is actually a different process and there are
various factors affecting the rate of evaporation. In this lesson, you have learned six
differences and six factors respectively.
Liquid
Melting
Boiling
Freezing
Solid
Evaporation
13
Condensation
Vapour
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Melting, Boiling and Evaporation
Solid
Liquid
Vapour
Activity 1: Discuss in pairs, the characteristics of a solid, liquid and
vapour in terms of the molecular arrangement and movement
in the table above. (3 minutes)
Be prepared to share your answers with the rest of the class.
14
Chia Guo Hao
054396H23
Melting:
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Melting is the change of state from ____________________ without a
____________________________
Freezing:
Freezing is the change of state from ___________________ without a
____________________________
Melting Point: The temperature point where ________________________________
Melting (Freezing) __________________ energy and the heat __________________
in the process is called the latent heat of fusion. The energy will be used to ________
___________ bonds for the matter.
Purely Solid
Melting Curve of Ice
A-B
30
Mixture of
Solid and
Liquid
25
B-C
Purely Liquid
o
Temperature ( C)
20
15
C-D
10
Mixture of
Liquid and
Vapour
5
D-E
0
Purely
Vapour
0
5
10
15
20
-5
25
30
E-F
Time (Minutes)
Time (min)
Temperature
(oC)
Activity 2: From the data collected by your friends, quickly sketch a
melting curve in the space provided above and label the
graph according to the labels given on the right.
15
Chia Guo Hao
054396H23
Boiling:
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Boiling is the change of state from ____________________________
without a ______________________________
Condensation: Condensation is the change of state from _______________________
without a ______________________________
Boiling Point: The temperature point where ________________________________
Boiling (Condensation) ___________________ energy and the heat ______________
____________ in the process is called the latent heat of vaporization. The energy will
be used to ___________________ bonds for the matter.
Purely Solid
Freezing Curve of Water
120 A
100
Mixture of
Solid and
Liquid
C
B
o
Temperature ( C)
80
Purely Liquid
60
40
Mixture of
Liquid and
Vapour
20
D
0
0
10
20
30
40
-20
E
50
60
Purely
Vapour
F
Time (Minutes)
Activity 3: Boiling/Condensation is similar to melting/freezing. Discuss
in pairs how would you complete the blanks above by
inferring from melting and freezing or otherwise. (3
minutes).
Be prepared to share you answers with the rest of the class.
16
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Evaporation: Evaporation is the change of state of a liquid into its vapour at ______
_______________. Evaporation requires energy and heat is absorbed
from _____________________ and it occurs only at the ___________
___________________ of the liquid.
Activity 4: Watch the video of a pot of water boiling and compare it to a
bowl of water evaporating. Can you pick out the differences
between boiling and evaporation to complete the figure and
table below? (3 minutes)
Be prepared to share your solutions with the class
Boiling
Differences
Evaporating
Comparing Boiling and Evaporation
Boiling
Evaporation
Temperature
Occurrence
Bubbles
Supply of Heat
Process
17
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Factors affecting rate of evaporation
Temperature
__________ the temperature of liquid ____________ rate of
evaporation as the liquid molecules are _________________
Humidity is a measure of the amount of ______________ our
Humidity of
present in the air. The ______________ the humidity, the
surrounding
___________________ is present in air and the evaporation
rates become _______________
Exposed surface
area of liquid
The larger the exposed surface area of the liquid, the
__________ the rate of evaporation will be since evaporation
_________________________________________________
Movement of air
Moving air (wind) ___________ the molecules of liquid as
above surface of
soon as it escapes to become vapour thus ___________ the rate
liquid
Pressure
of evaporation
Lower atmospheric pressure _________ the rate of evaporation
as it is ________________ for liquid molecules to escape
Different types of liquid have _________________________
that will affect the rate of evaporation. For example, ________
Nature of liquid
hardly evaporate at room temperature due to the ___________
______________ while volatile liquid such as _____________
______________ evaporates quickly
Modern Application of Evaporation
1. Coffee shop uses a fan that sprays mist of water droplets to cool down customers
and the surrounding during a hot day. When the water droplets evaporate, it
_______________________________ from the customers and the surroundings
thus cooling the area down.
2. Hair dryer makes use of hot air to blow dry our hair. The hot ______________
___________________________ to increase the rate of evaporation, hence it can
dry our hair quickly.
3. In Singapore, we hang wet clothes on poles outside the HDB flat to dry them. The
sun will _________________________________________ to increase the rate of
evaporation. Finally, clothes are hanged in such a way _____________________
________________________________
18
Chia Guo Hao
054396H23
Microteaching & Lesson Planning
Melting, Boiling and Evaporation
QCP521
Due: 15/10/05
Summary: Melting, Boiling and Evaporation
In this chapter, you learned that melting, freezing, boiling and condensation are
processes when matter changes from one state to another at any temperature. The
temperature may or may not vary during these processes. You also learn that heat
energy released for melting and boiling is used to break the inter-molecular bonds
while heat energy absorbed for freezing and condensation when intermolecular bonds
are being formed. The processes can be observed through the temperature against
distance graph for cooling and heating of matter
Evaporation, though similar to boiling, is actually a different process and there are
various factors affecting the rate of evaporation. In this lesson, you have learned five
factors and four differences.
Liquid
Solid
Vapour
19