4.2 The states in which matter occurs

Natural sciences

Grade 4

Matter, substances and materials

Module 52

The states in which matter occurs

Activity:

To discuss the three states in which matter occurs

[lo 1.2.2, 1.2.3, 1.3.1]

Task

See if you can unscramble the following groups of letters to make the names of the three states of matter.

1. o i l d s

2. d q l u i i

3. s a g

Let’s look at the properties of each state. Which state are we speaking of when we say:

It has its own shape, has mass and occupies space.

It does not have its own shape but can be seen and occupies space.

It does not have its own shape and can’t be seen.

Matter can change its shape

What substance can change into all three states of matter?

Try the following (3) :

Make interesting ice cubes in the freezer. Put leaves or flowers in each container with the water. Wait until the water has frozen.

The water has now become hard. What do we call it?

We call it ............................................ Draw it.

Take the ice cubes out of the containers and put four in a pot on the stove. Put another four in a different pot. Do not put them on the stove. Now turn on the stove. What happens to the ice cubes on the stove?

The ice cubes have changed into a different state. What do we call them now?

We call it ............................................ Draw it.

What happens to the ice cubes that weren’t on the stove? Why did the ones on the stove melt quicker?

Now let the water in the pot on the stove boil.

What happens to the water now? What do we call it?

We call it ............................................ Draw it.

What is the temperature when water boils?

What is the temperature when water freezes?

Try the following (4):

Take four ice cubes. Place one in the fridge, one on a table, one next to a burning candle and one in a glass container. Each half-hour observe what has happened to the ice cubes. Draw a graph on the board to show the different tempos at which the ice cubes melt.

What is your conclusion?

My conclusion is:

Let’s have some fun. Divide the class into three groups. One group is the solids, another the liquids and the third is the gases. Each group makes a play to show its properties. Use music, discarded items, strange costumes and loads of creativity.

Some changes in matter are temporary, others are permanent

Try the following (5):

Bring ten different containers that can hold water to school. Take one glass of water and in turn pour it into each container. Notice how the water changes form.

Now discuss how the following change:

snow on the mountains;

puddles on the playground;

washing;

steam in a shower;

ice cubes.

Assessment

LEARNING OUTCOME 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.

Assessment Standard

We know this when the learner

• conducts investigations and collects data:

• tries own idea of how the materials might respond;
• perseveres or repeats the activity in different ways, experiencing the phenomenon in other ways.
• evaluates data and communicates findings:

1.3.1 describes own perceptions of the event, relating to the purpose of the investigation.

Memorandum

Three forms in which matter occurs

• Task: See if you can sort out the numbered letters to identify three forms of matter:

1. l o s I d : solid
2. d I l I q u : liquid

3. s a g: gas

Let’s look at the properties of each state.

Which one are we talking about now?

• Own shape, has mass, visible, occupies space: solid
• Doesn’t have own shape, visible, occupies space: liquid
• Doesn’t have own shape, invisible: gas

Matter can change shape

Try the following (3)

• What substance can be in all three states? Draw each one in its block and make a caption for each one.Answer:
• Water can be in all three states. Learners draw a glass of water with the caption: Liquid. Draw an ice cube with the caption: Solid. Draw a kettle boiling with steam with the caption: Gas.

Mr Brain Cell:

• What is the temperature of boiling water?
• What is the temperature at which water freezes?Answer:
• 100 degrees Celsius
• 0 degrees Celsius

Try the following (4)

• Conclusion: The one close to the burning candle melts the quickest, the one in the fridge melts the slowest. Heat melts ice quickly, cold allows it to melt slowly.

Try the following (5)

• Let learners do the experiment themselves.
• Changes:
• Snow on the mountains: The solid changes to a liquid.
• Puddles on the mountain: Liquid changes to gas
• Washing: Liquid changes to gas
• Condensation in the shower. Gas changes to liquid.
• Ice cube: Solid changes to a liquid.