Year 4 Science: Comparing and grouping materials
Part of the Year 4 Science solids, liquids and gases chapter. Chapter overview · whole chapter on one page
Comparing and grouping materials
To group materials, compare the features of each one. The first question is: does it keep its own shape? The second question is: does it flow? The third question is: does it spread out to fill the container? The table sorts 11 materials into the three groups.
| Material | Solid, liquid or gas? |
|---|---|
| wood | solid |
| ice | solid |
| metal spoon | solid |
| rock | solid |
| plastic bottle | solid |
| water | liquid |
| milk | liquid |
| cooking oil | liquid |
| orange juice | liquid |
| air | gas |
| bubbles in fizzy water | gas |
The same materials, grouped into three columns.
| Solids | Liquids | Gases |
|---|---|---|
| wood | water | air |
| ice | milk | bubbles in fizzy water |
| metal spoon | cooking oil | |
| rock | orange juice | |
| plastic bottle |
Key ideas
- Group materials by comparing their features.
- A solid keeps its shape. A liquid flows and takes the shape of its container. A gas spreads out to fill it.
- Each material belongs to one group only.
- Count the materials in each group to compare the groups.
Method. Count the solids in the table.
- Read the table. The solids are wood, ice, metal spoon, rock and plastic bottle.five names
- Count them. There are five solids in the table.5
- Write the answer. 5
Check. The table has 11 materials in all. ✓
Method. Count the gases in the table.
- Read the table. The gases are air and the bubbles in fizzy water.two names
- Count them. There are two gases in the table.2
- Write the answer. 2
Check. Two gases is the smallest group. ✓
Method. Compare the three counts.
- Compare the counts. Solids 5, liquids 4 and gases 2.5, 4, 2
- Choose the biggest. The biggest count is 5, for solids.solids
- Write the answer. solids
Check. Five is more than four, and more than two. ✓
Watch out
Watch out: a bubble in fizzy water is a gas, even though the water around it is a liquid. Each material is grouped by the state of the material itself.
Try it at home or school (with a grown-up). Look at five things in your kitchen, with a grown-up. Sort them into solids, liquids and gases, and write one feature you used for each group. Do not taste any of them.
Exam tip
Grown-up tip. Ask: “Does it keep its shape? Does it pour? Does it spread out?” Let your child use the three questions to sort each thing.
Exercise 6D Comparing and grouping materials
Method. Read the table.
- Find the two materials. The plastic bottle is a solid, and milk is a liquid.solid
- Name the solid. So the solid is the plastic bottle.plastic bottle
- Write the answer. plastic bottle
Check. Milk flows, so it is a liquid. ✓
Method. Count the solids.
- Count them. Wood, ice, metal spoon, rock and plastic bottle are the solids.five
- Write the answer. 5
Check. Five solids in the table. ✓
Method. Count the liquids.
- Count them. Water, milk, cooking oil and orange juice are the liquids.four
- Write the answer. 4
Check. Four liquids in the table. ✓
Method. Count the gases.
- Count them. Air and the bubbles in fizzy water are the gases.two
- Write the answer. 2
Check. Two gases in the table. ✓
Method. Add the three groups.
- Add the groups. Five solids, four liquids and two gases.5 + 4 + 2
- Find the total. The total is 11 materials.11
- Write the answer. 11
Check. The table has 11 materials. ✓
Method. Compare the three counts.
- Compare the counts. Solids 5, liquids 4 and gases 2.5, 4, 2
- Choose the smallest. The smallest count is 2, for gases.gases
- Write the answer. gases
Check. Two is less than four and five. ✓
Method. Check the table.
- Check the table. Ice is listed in the solid group.solid group
- Decide. So the answer is yes.yes
- Write the answer. yes
Check. Ice keeps its shape. ✓
Method. Think about how orange juice behaves.
- Think about the juice. Orange juice can be poured, so it flows.flows
- Name the group. A material that flows is a liquid.liquid
- Write the answer. liquid
Check. Orange juice is listed as a liquid. ✓
Method. Check both materials.
- Check wood. Wood is a solid.solid
- Check metal. Metal is a solid too, so both are in the solid group.both solid
- Decide. So the answer is yes.yes
- Write the answer. yes
Check. Both keep their shape and are hard. ✓
Method. Think about the first question to ask.
- Think about the features. The first question is whether it keeps its own shape.own shape
- Write the feature. Checking the shape first helps to separate solids from the others.separate
- Write the answer. Accept any feature that can be checked, such as whether it keeps its shape, or whether it flows.
Check. A good feature can be checked by looking or pouring. ✓
Method. Think about what a group is for.
- Think about the group. Materials in the same group share a feature.share
- Write the reason. So we can predict how each material will behave.predict
- Write the answer. Accept any sentence that says materials with the same features behave in the same way, so they can be grouped together.
Check. Shared features make groups useful. ✓