Neda Grose, Michael Doyle
1. Year levels
2. Theme of unit
3. Curriculum links of the activity
4. Unit Links to National Statements of Learning for Science
5. Prior understandings recommended for the activity
6. Teacher Background Information
7. Equipment and Materials
8. Safety
9. Lesson Steps
Years 4 and 5
Water is essential to life. As humans, we not only drink water, we use it for cooking, hygiene, recreation and agriculture. Australia is a dry continent with an expanding population, and how we use water has become increasingly important. Water is a scarce and finite resource. Around 70 per cent of the Earth's surface is covered by water, in oceans, seas, lakes, rivers and swamps, however, less than one per cent is available as fresh, drinkable water.
Water has a wide range of properties, many of which can be investigated by primary schools students using various simple investigations using everyday materials. Investigations that can be used include:
· Has something been living in your water This activity looks at how ammonia affects water quality.
· Whats in a colour? This activity separate colours from water soluble felt pens using paper chromatography
· Conductivity in water This activity introduces conductivity as a method of analysing water.
· Stranded This activity looks at filtration
· What do different chemicals do to water? This activity looks at the effect of household chemicals on the environment
· Are you balanced? This activity looks at pH
· Science
· Interpersonal development
· English/Literacy
· Mathematics/Numeracy
· Information and Communications Technology (ICT)
· Study of Society and Environment or HSIE
· Health and Physical Education
| Science as a human endeavour | |
| Broad learning objectives · Students recognise scientific aspects of their everyday activities, application of science in their own lives and the place of science in the work of people in their community. · Students show and share responsibility for the quality of their immediate environments and for resource conservation |
Concepts developed · Science forms a part of our everyday lives · Changing water quality through human activity |
| Science as a way to know | |
| Broad learning objectives · Students begin asking questions and making predictions related to their everyday experience. · Students revisit their questions in light of their results. They share findings, talk about the way in which the investigation could be changed and begin to consider fairness of tests |
Concepts developed · Scientists use particular processes and procedures in their work · Everyday and scientific language is used to describe, share and explain scientific observations and findings · Changes can be observed and investigated through the collection, recording and presenting of data Experiments are devised to predict, explore and question the world around us |
| Science as a body of knowledge | |
|
Matter | |
|
Broad learning objectives · Students observe and describe how changing familiar materials changes their properties. |
Concepts developed · Properties of water · Changes in properties of water |
|
Living Things | |
|
Broad learning objectives · |
Concepts developed · Humans can affect the environment and the survival of living things · Resources are finite and need to be managed and preserved for future generations |
Prior to undertaking this activity, it is recommended that students will have developed fundamental ideas of water, including the water cycle, the properties of water and the source and use of water. It is also recommended that students have had opportunities to work and think scientifically.
Water is a unique substance whose properties allow many things to be carried by it. Water can dissolve many substance however not all solids can be dissolved in water. Solids like silica and clay, the common components in soil are not soluble in water. Water can become dirty looking with fine particles of soil suspended in the water. Water can be separated from the substances suspended in it by passing it through things with tiny holes like paper.
Oils and fats are long chain hydrocarbon molecules. The surface of the oil molecules repels water and so the oils collect in globs away from the water. Oil is less dense (lighter) than water so it will float on the top of the water. Oils can be separated from water as the oil will form a layer on the top of the water. Food dye will only dissolve in water and not oil.
An extension activity might be to make a filter for dirty water using different sizes of sand layered into a jar.
Aim
To show that solids and oils can be separated from water.
Activity Information
a). The solids will separate at different rates according to their sizes.
b). Fine clay particles may not be filtered out.
c). The oils will float on top of the water.
Focus Questions
Outline
Not all water is clean and clear, sometime it is mixed with dirt. It is possible to remove the dirt and get clean water again?
Part A
1. When you poured the dirty water into the tin was there anything in the bottom of the first jar?
There should be some heavy particles, sand
2. What colour is the water in the second jar?
Clear
3. Was there anything in the cup after the water had gone?
Mud
4. Look at the cup from the side can you see layers? Why are they there?
Layers of different size particles depending on how much was left in the jar in question . The biggest particles will be on the bottom.
Part B
1. Does the food dye stay in one layer or go into both?
It should be in the water, the bottom layer.
2. Which container has the water in it?
The container which collected the liquid from the bottom of the cup.
· Jars or clear plastic cups
· Filter paper
· A clear plastic pet bottle with a small hole in the cap and the base cup off.
· Some dirt.
· Some clean water.
· Some food dye
· Some cooking oil
· Do not put anything in you mouth or eyes.
· Check the tin has no sharp edges.
Part A
1. In the first jar, mix some clean water and some dirt and stir well.
2. Carefully cut some filter paper to fit in the bottom of the plastic cup. Make sure it is as big as possible but with no wrinkles in it.
3. Put the tin on top of the second jar.
4. Slowly pour the dirty water into the tin.
5. Watch the water coming out the bottom of the cup into the second jar.
Part B
1. In the first jar put some cooking oil
2. Add one drop of food colouring.
3. Carefully pour in an equal amount of clean water and mix gently.
4. Allow to stand until two layers form.
5. Using the bottle put your finger over the hole in the cap and get your partner to pour the oily water into the cup.
6. When the layers form again hold the cup over the second jar and let the coloured layer come out of the bottom of the cup into the jar.
7. Stop the flow before any of the top layer comes out.
8. Trip the remaining liquid into the other jar.
9. Dip a finger into each jar to work out which layer is the water.