Quick Summary
- Matter is anything with mass that takes up space
- Matter exists in three states: solid, liquid, gas (plus plasma)
- All substances around us are forms of matter
- Matter has both mass and volume
- Not everything is matter (light, sound, thoughts are not matter)
What is Matter?
Matter is the scientific name for all physical things around you. Your desk is matter. The pure water you drink is matter. The air you breathe is matter. Even your body is matter.
For something to be called matter, it must have two properties. First, it must have mass. Mass is how much material something contains. You measure mass in kilograms or grams. Second, it must occupy space. This means it takes up room and has volume.
Everything you can touch or see is made of matter. The chair you sit on, the book you read, the food you eat at lunch break, and the uniform you wear are all matter. Even things you cannot easily see, like air, are still matter because they have mass and take up space.
Properties of Matter
1. Mass
Mass is the amount of matter in an object. When you step on a scale, you are measuring your mass (though the scale shows weight). A truck has more mass than a bicycle. A bag of rice has more mass than a bag of garri.
Mass does not change when you move to different places. If you have a mass of 50 kg in Lagos, you still have 50 kg in Abuja or Kano. Mass is different from weight. Weight changes with gravity, but mass stays the same.
2. Volume (Occupies Space)
Volume is the amount of space matter takes up. A big water tank has more volume than a bucket. Your school building has more volume than your classroom.
You measure volume in liters for liquids and cubic meters (m³) or cubic centimeters (cm³) for solids. When you buy one liter of groundnut oil or two liters of petrol, you are measuring volume.
States of Matter
Matter exists in different forms called states. The three main states you will study for WAEC are solid, liquid, and gas. There is also a fourth state called plasma, but it is less common in everyday life.
1. Solid State
Solids have a fixed shape and fixed volume. A stone, a chair, a pencil, and a block of ice are all solids. Solids keep their shape unless you break or melt them.
In solids, particles are packed very close together. They vibrate in place but do not move around freely. This is why solids are hard and keep their shape. Examples in Nigeria include yam tubers, metal gates, cement blocks, and wooden furniture.
2. Liquid State
Liquids have a fixed volume but no fixed shape. They take the shape of any container you pour them into. Water, palm oil, kerosene, and soft drinks are all liquids.
If you pour water into a cup, it becomes cup-shaped. If you pour the same water into a bucket, it becomes bucket-shaped. The volume stays the same, but the shape changes. In liquids, particles are close together but can slide past each other. This is why liquids can flow.
3. Gas State
Gases have no fixed shape and no fixed volume. They spread out to fill any container completely. The air you breathe is a mixture of gases. Cooking gas (LPG) and car exhaust are also gases.
In gases, particles move very fast and spread far apart. This is why you can smell food cooking in the kitchen even when you are in the sitting room. The gas particles from the food spread through the air. Gases can be compressed (squeezed into smaller spaces), which is why cooking gas fits in cylinders.
4. Plasma State
Plasma is the fourth state of matter, but you rarely see it in daily life. It exists at very high temperatures. Lightning, the sun, and fluorescent lights contain plasma. In plasma, atoms break apart into charged particles. You do not need to know much about plasma for O-Level exams, but it exists.
Comparison Table: States of Matter
| Property | Solid | Liquid | Gas |
|---|---|---|---|
| Shape | Fixed/Definite | Takes container shape | Takes container shape |
| Volume | Fixed/Definite | Fixed/Definite | Fills container completely |
| Particle Arrangement | Very close, packed tight | Close but can slide | Very far apart |
| Particle Movement | Vibrate in place | Move around freely | Move very fast, spread out |
| Compressibility | Cannot compress | Cannot compress easily | Can compress easily |
| Examples in Nigeria | Yam, iron, wood, salt | Water, oil, milk, petrol | Air, cooking gas, smoke |
Examples of Matter in Daily Life
In Your Home
- Solids: Furniture, plates, pots, walls, cement floor, clothes, shoes
- Liquids: Water, palm oil, kerosene, liquid soap, soft drinks
- Gases: Air in rooms, cooking gas (LPG), gas from generator exhaust
In Your School
- Solids: Desks, chairs, chalkboard, books, pen, pencil, building walls
- Liquids: Water from taps, ink in pens, paint on walls
- Gases: Air you breathe, oxygen in chemistry lab, carbon dioxide you exhale
In the Market
- Solids: Rice, beans, yam, plantain, fish, meat, tomatoes, fruits
- Liquids: Groundnut oil, palm oil, zobo drink, fresh milk
- Gases: Air around market, smoke from fires
What is NOT Matter?
Not everything is matter. Some things have no mass or do not occupy space. These are NOT matter:
- Light: You can see light, but it has no mass and does not occupy space in the way matter does. Sunlight and electric light are not matter.
- Sound: You can hear sound, but sound is just vibrations moving through air. Sound itself is not matter.
- Heat: Heat is energy, not matter. When something feels hot, that is energy moving, not matter.
- Thoughts and feelings: Love, happiness, ideas, and memories are not matter. They have no mass and take up no space.
- Time: You cannot touch or measure the mass of time. Time is a concept, not matter.
How Matter Changes State
Matter can change from one state to another when you heat it or cool it. These changes have special names:
- Melting: Solid to liquid (ice to water, butter melting in hot sun)
- Freezing: Liquid to solid (water to ice in freezer)
- Evaporation: Liquid to gas (water drying from wet clothes, petrol evaporating)
- Condensation: Gas to liquid (water droplets on cold bottle, steam becoming water)
- Sublimation: Solid directly to gas (camphor balls, dry ice)
- Deposition: Gas directly to solid (frost forming on cold surfaces)
These state changes are physical changes, not chemical changes. The substance stays the same. Water is still water whether it is ice, liquid water, or steam. Only the arrangement of particles changes.
Common Exam Mistakes About Matter
WAEC Chief Examiners report these common student errors:
- Confusing mass and weight: Students write “matter has weight” when they should write “matter has mass.” Weight depends on gravity; mass does not.
- Wrong definition: Many students write “matter is anything that can be seen.” This is wrong. Air is matter, but you cannot see it.
- Saying light or sound is matter: Light, sound, and heat are NOT matter. They are forms of energy.
- Forgetting both properties: Matter must have BOTH mass AND volume. Do not forget to mention both.
- Using “space” without explaining: “Occupies space” means it has volume. Be clear about this.
- Poor examples: Use concrete, everyday examples. “Thing” is too vague. Say “chair” or “water.”
Practice Questions
Multiple Choice Questions
1. Which of the following is NOT matter?
a) Air
b) Water
c) Sound ✓
d) Salt
2. Matter is defined as anything that:
a) Can be seen and touched
b) Has mass and occupies space ✓
c) Has color and shape
d) Can be measured
3. Which state of matter has a definite shape and definite volume?
a) Liquid
b) Gas
c) Solid ✓
d) Plasma
4. The process of changing from liquid to gas is called:
a) Melting
b) Condensation
c) Evaporation ✓
d) Freezing
5. Which of these is an example of matter in the gaseous state?
a) Ice
b) Water
c) Steam ✓
d) Salt
Essay/Theory Questions
1. (a) Define matter. (2 marks)
(b) State TWO properties of matter. (2 marks)
(c) Give THREE examples of matter in the liquid state found in Nigerian homes. (3 marks)
Examiner’s Tip: For (a), mention both mass and space. For (c), use specific Nigerian examples like palm oil, kerosene, not just “liquid.”
2. (a) Distinguish between solid and liquid states of matter. (4 marks)
(b) Give TWO examples each of solid and liquid. (2 marks)
Examiner’s Tip: “Distinguish” means show differences. Compare shape and volume properties. Use a table if possible.
3. Explain why air is considered matter even though it cannot be seen. (4 marks)
Examiner’s Tip: Mention that air has mass (can be weighed) and occupies space (fills balloons, rooms). Give practical examples.
4. (a) List FOUR examples of matter. (2 marks)
(b) State THREE things that are NOT matter. (3 marks)
Examiner’s Tip: “List” and “state” need no explanation, just direct answers.
Memory Aids
To remember the definition of matter: “M-V”
- M – Has Mass
- V – Has Volume (occupies space)
To remember states of matter: “S-L-G-P”
- S – Solid (fixed shape, fixed volume)
- L – Liquid (no fixed shape, fixed volume)
- G – Gas (no fixed shape, no fixed volume)
- P – Plasma (special high-energy state)
State changes: “MEFCSD”
- M – Melting (solid → liquid)
- E – Evaporation (liquid → gas)
- F – Freezing (liquid → solid)
- C – Condensation (gas → liquid)
- S – Sublimation (solid → gas)
- D – Deposition (gas → solid)
What is NOT matter: “L-S-H-T”
- L – Light
- S – Sound
- H – Heat
- T – Thoughts/Time
Related Topics
- States of matter and their properties
- Changes of state (melting, freezing, evaporation, condensation)
- Kinetic theory of matter
- Physical and chemical changes
- Measurement of mass and volume
- Particle theory of matter
- Elements, compounds, and mixtures