Yishun Primary 4 Science tuition should help students understand matter by comparing the properties of solids, liquids and gases and tracing what changes when a substance changes state.
This rebuilt legacy URL now owns one distinct P4 Science job: state → property → particle-level classroom model → state change → evidence. Old result promises, mixed-grade copy and implied Yishun-centre claims have been removed.
eduKateSG does not claim a current Yishun branch. Current centres are at 83 Punggol Central, Singapore 828761 and 8 Fourth Avenue, Singapore 268674. Selected Primary Science classes run in focused 3-pax small groups, typically 1.5 hours.
The Direct Answer
At Primary 4, students should be able to compare the three common states of matter:
- solid: fixed shape and fixed volume under ordinary classroom conditions;
- liquid: no fixed shape but fixed volume; takes the shape of its container;
- gas: no fixed shape and no fixed volume; spreads to fill available space.
State of matter is defined by observable properties, not by whether the substance feels “hard”, “wet” or “invisible”.
Solids
A solid keeps its own shape unless a force changes it. A wooden block, metal spoon and ice cube are all solids even though they differ in hardness, colour and temperature.
Liquids
A liquid flows and takes the shape of its container while keeping approximately the same volume under the classroom conditions studied.
Water in a cup and water in a bottle have different shapes but the same amount of water if no water is added or removed.
Gases
A gas spreads through available space. Air inside a syringe can be compressed more easily than a liquid because gas particles are much farther apart in the simple school model.
Worked Example: Ice, Water, Water Vapour
The same substance—water—can exist in different states.
- ice = solid;
- liquid water = liquid;
- water vapour = gas.
The chemical substance remains water; the state changes.
Melting
Melting is the change from solid to liquid when the substance gains enough heat under suitable conditions.
Freezing
Freezing is the change from liquid to solid when heat is removed and the substance reaches its freezing condition.
Evaporation
Evaporation changes liquid into gas at the surface and can occur below boiling point.
Students should not define evaporation as “water disappearing”.
Condensation
Condensation changes gas into liquid when water vapour loses heat under suitable conditions.
Droplets outside a cold cup come from water vapour in the surrounding air, not from liquid leaking through the cup.
Worked Example: Shape vs State
A lump of clay can be reshaped. It is still a solid because it does not flow to take the shape of the container by itself.
This separates can change shape under force from has no fixed shape.
Worked Example: Powder
Sand or sugar can be poured and can take the shape of a container as a collection. But each grain is a small solid.
This is a useful boundary case because “can be poured” does not automatically mean liquid.
Worked Example: Air in Balloon
Air takes the shape of the balloon and expands through the available space. The balloon contains gas even though the gas is not directly visible.
State Change Is Reversible in Many Cases
Ice can melt to water and water can freeze back to ice. The cycle shows state change without needing a new substance.
Students should distinguish physical state change from irreversible chemical change, though detailed chemistry comes later.
The Property Table
| State | Fixed shape? | Fixed volume? | Flows? |
|---|---|---|---|
| Solid | Yes | Yes | No |
| Liquid | No | Yes | Yes |
| Gas | No | No | Yes/spreads |
The Same-Substance Test
Ask whether the substance identity stays the same through the state change.
Ice → water → water vapour is still water in different states.
The Heat-Direction Test
Melting/evaporation involve gaining heat.
Freezing/condensation involve losing heat.
This links the Matter topic to the separate P4 Heat topic without duplicating it.
The Observation Test
Use actual evidence:
- shape changes with container;
- volume remains;
- gas expands;
- solid melts;
- droplets form.
Then infer the state or process.
Common P4 Matter Failure Modes
| Symptom | Issue | Repair |
|---|---|---|
| Powder called liquid | Bulk flow confused with particle state | Examine individual grains |
| Soft solid called liquid | Hardness confused with state | Use shape/volume criteria |
| Gas said to have no mass because invisible | Visibility confused with existence | Use balloon/syringe evidence |
| Evaporation = boiling | Processes merged | Use puddle example |
| Condensation source misunderstood | Water pathway wrong | Trace vapour from air |
P4 Curriculum Context
MOE’s current Primary Science syllabus places Matter at Primary 4. Official reference: MOE Primary Science Syllabus.
Why Three Students Helps
One student classifies a material, one names the property used and the third supplies a boundary case such as sand, clay or air. The tutor checks whether the rule survives.
When Yishun Primary 4 Families May Consider This Support
- State is confused with hardness or visibility.
- Powders and soft solids cause misclassification.
- State-change names are memorised without heat direction.
- Condensation and evaporation explanations are weak.
What Progress Should Look Like
A stronger P4 learner can classify states from observable properties, explain common state changes and handle boundary cases without relying on superficial clues.
Independent location notice: eduKateSG does not claim a current Yishun branch. Current centres: 83 Punggol Central, Singapore 828761 and 8 Fourth Avenue, Singapore 268674. Contact +65 8823 1234.