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Natural sciences

Grade 8

Matter: classification

Module 15

Phase changes of matter

Prior Knowledge:

  • Matter has three phases: solid substances, liquid substances and gases

Class activity: reading skill

In the heart of a Cape winter

Adventurers went camping in the Cedar Mountains.

The night brought a fall of snow that

Glistened in the early morning light.

Slowly, surely, the ice was melted by the wintry sun

And water ran in rivulets to the riverbed.

A camper scooped up a billycan of the stream’s water

He struck a match to light his fire

And soon steam billowed from his billycan!

1. Name all the phases of water mentioned in the text – list all the descriptive words.

2. Name the source of energy that causes:

a. the ice to melt

b. the water to steam

3. a. In which phase do particles of water have the greatest freedom of movement?

b. Which phase presents the strongest attraction between particles of water?

4. The phases of water are also an important part of nature, as the WATER CYCLE becomes possible because of it. Fill in the following:

The Water Cycle

6. The following illustrations represent phase changes. Explain what happens to the water in each instance:

Assessment of reading skills

Were you able to make the correct deductions from the text?

[LO 2.3]


Find out the following:

(You could use the given web addresses or any other source for research.)

Why ice floats on water.– www.geocities.com (iceberg+ float)

How snowflakes are formed.– google.com (snowflakes)– www.edu.pe.ca/rural/chemist

Why alcohol (as in Schnapps or Witblits) does not freeze in the freezer.

What the boiling point of fluids like cooking oil and alcohol is.– www.ucc.ie – (boiling points)

Paste or write the information on the facing page.

Assessment for assignment

Has the information been collected and recorded?

[LO 1.3]

7. Each substance has its own boiling and freezing point.

Water freezes at

Water boils at

 Do you know the following? 

A fourth phase of matter has been discovered – it is known as PLASMA.

It only occurs at excessively high temperatures and in stars.

Read more about PLASMA!



Learning outcomes 1: Scientific investigations

The learner will be able to act confidently on curiosity about natural phenomena, and to investigate relationships and solve problems in scientific, technological and environmental contexts.

We know this when the learner

1.3 is able to evaluate data and communicate findings.

Learning outcomes 2: Constructing science knowledge

The learner will know and be able to interpret and apply scientific, technological and environmental knowledge.

We know this when the learner

2.3 is able to interpret information.


1. snow; ice (solid substance) – water; river water (liquid) – steam (gas)

2. a) sun b) fire

3. a) steam (gas) b) snow/ice

4. spaces smaller in solid substances

5. 1 – evaporation; 2 – transpiration; 3 – cloud formation / condensation

4 – precipitation (rain, snow, etc.)

6. condenses; melts; freezes (crystallises); evaporates

Questions & Answers

How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
characteristics of micro business
for teaching engĺish at school how nano technology help us
How can I make nanorobot?
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
how can I make nanorobot?
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
what is the actual application of fullerenes nowadays?
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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Source:  OpenStax, Natural sciences grade 8. OpenStax CNX. Sep 12, 2009 Download for free at http://cnx.org/content/col11050/1.1
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