Properties and Changes of Materials
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
Reversible changes (dissolving, melting, evaporating)
SubtopicReversible changes (dissolving, melting, evaporating) under Properties and Changes of Materials for Grade 5 IGCSE.
Preview questions (no answers)
- 1.
When wet clothes are hung outside in the wind, they dry. This is because the water:
A.Melts into the clothes
B.Dissolves into the fabric
C.Evaporates into the air
D.Freezes into the air
- 2.
Which of these is the best description of a reversible change?
A.A change that happens very quickly
B.A change that cannot be undone
C.A change that results in a new substance
D.A change that can be undone to get the original material back
- 3.
In a sugar solution, why does the sugar seem to disappear?
A.It turns into gas
B.It breaks into tiny pieces too small to see
C.It is destroyed by the water
D.It floats to the top and escapes
- 4.
Which change can be reversed by simply cooling the material?
A.Cooking an egg
B.Burning a match
C.Melting chocolate
D.Toasting bread
- 5.
The diagram shows two processes where wax changes state. Which statement correctly describes what happens during these processes?
A.Process 1 is melting and requires adding heat energy.
B.Process 2 is freezing and requires removing heat energy.
C.Process 1 is freezing and requires removing heat energy.
D.Process 2 is melting and requires removing heat energy.
- 6.
What is the main difference between boiling and evaporation?
A.Boiling happens only at the surface; evaporation happens throughout.
B.Boiling requires a specific temperature; evaporation can happen at various temperatures.
C.Boiling is a chemical change; evaporation is a physical change.
D.Boiling is reversible; evaporation is not.
- 7.
If you want to separate a mixture of pebbles and sand, which method is best?
A.Dissolving them in water
B.Using a sieve with medium-sized holes
C.Evaporating the sand
D.Using a magnet
- 8.
A student measures the mass of a beaker of water and a spoonful of salt separately. The total mass is . After dissolving the salt in the water, what will the mass of the solution be?
A.B.Less than because the salt dissolved
C.More than because the salt and water combined
D.because of salt 'disappears'
- 9.
Why does a wet towel dry faster if it is spread out rather than left in a crumpled ball?
A.The surface area exposed to the air is greater, allowing more water particles to escape
B.The water particles are crushed together in a ball, making them harder to move
C.The heat cannot reach the center of a crumpled towel
D.Gravity pulls the water out of a spread-out towel more easily
- 10.
Which of these processes describes the change from a gas directly to a liquid?
A.Condensation
B.Evaporation
C.Sublimation
D.Solidification
Download the worksheet for Properties and Changes of Materials - Reversible changes (dissolving, melting, evaporating) to practice offline. It includes additional chapter-level practice questions.
Irreversible changes (burning, rusting, mixing acid and bicarbonate of soda)
SubtopicIrreversible changes (burning, rusting, mixing acid and bicarbonate of soda) under Properties and Changes of Materials for Grade 5 IGCSE.
Preview questions (no answers)
- 1.
Which of these is created when wood is completely burned in a fireplace?
A.Fresh wood
B.Ash
C.Liquid water
D.Oxygen
- 2.
What do we call a change that cannot be undone?
A.Reversible
B.Temporary
C.Irreversible
D.Physical
- 3.
Which material is used to coat some metals to prevent them from rusting?
A.Zinc
B.Paper
C.Salt
D.Sponge
- 4.
If you mix vinegar and baking soda in a sealed bag, why does the bag bulge?
A.The bag is getting heavier
B.The bag is getting hotter
C.The gas produced needs more space
D.The vinegar is turning into a solid
- 5.
If you mix an acid with bicarbonate of soda and keep the container open, what happens to the total mass of the materials in the container?
A.The mass increases as the reaction gains energy.
B.The mass decreases as the gas produced escapes into the air.
C.The mass stays exactly the same because no atoms are lost.
D.The mass doubles because two things were mixed together.
- 6.
In which of the following scenarios is an irreversible change occurring?
A.Melting an ice cream cone on a hot day.
B.Stretching a rubber band.
C.Burning a piece of toast in a toaster.
D.Dissolving a spoonful of honey in warm milk.
- 7.
What evidence do we have that mixing bicarbonate of soda and vinegar is a chemical change?
A.The color stays the same.
B.A new gas is produced, which is a new substance.
C.The powder simply disappears into the liquid.
D.The volume of the liquid remains exactly the same.
- 8.
What happens to the atoms of the original materials during an irreversible chemical change like rusting?
A.They are rearranged and bonded in new ways to form different substances.
B.They are destroyed and replaced by new atoms of the products.
C.They melt into a liquid and then disappear into the air.
D.They stay exactly the same and just change their color.
- 9.
If you burn a piece of charcoal in the open air, the ash left behind weighs only . Why is this not a violation of the Law of Conservation of Mass?
A.The other of mass was released into the air as carbon dioxide and smoke.
B.The Law of Conservation of Mass only applies to physical changes.
C.Charcoal is mostly made of air, which has no mass when it burns.
D.The heat of the fire destroyed the mass of the charcoal.
- 10.
Which of these is an example of an irreversible change that occurs very slowly over many weeks?
A.The rusting of a garden gate.
B.The burning of a matchstick.
C.The fizzing of a vitamin tablet in water.
D.The melting of a glacier.
Download the worksheet for Properties and Changes of Materials - Irreversible changes (burning, rusting, mixing acid and bicarbonate of soda) to practice offline. It includes additional chapter-level practice questions.
Separating mixtures (filtering, sieving, and decanting)
SubtopicSeparating mixtures (filtering, sieving, and decanting) under Properties and Changes of Materials for Grade 5 IGCSE.
Preview questions (no answers)
- 1.
If you have a mixture of oil and water, the oil floats on top. How can you separate most of the oil?
A.Filtering it through paper
B.Sieving it
C.Decanting the oil into another container
D.Freezing it
- 2.
What is the first step in decanting a sand and water mixture?
A.Pour it immediately
B.Let the mixture sit until the sand settles
C.Boil the water
D.Stir it as fast as possible
- 3.
Which property is NOT used to separate mixtures by sieving, filtering, or decanting?
A.Particle size
B.Solubility
C.Magnetism
D.Density (sinking/floating)
- 4.
When filtering, where is the residue collected?
A.In the bottom beaker
B.On the filter paper
C.In the glass rod
D.On the table
- 5.
In a mixture of gravel, sand, and sugar, which component could be separated first by using a sieve?
A.The sugar
B.The gravel
C.The sand
D.None of them
- 6.
Which of the following would NOT be separated by a standard lab filter paper?
A.Sand and water
B.Chalk powder and water
C.Salt dissolved in water
D.Coffee grounds and water
- 7.
When separating two liquids like oil and water by decanting, which property allows the oil to be poured off easily?
A.Oil is thicker than water
B.Oil does not mix with water and floats on top
C.Oil has a different color than water
D.Oil is colder than water
- 8.
Why is it difficult to separate a mixture of milk and water using filtering, sieving, or decanting?
A.Milk is a solution where the particles are too small to be trapped by filters or sieves, and it does not settle into layers.
B.Milk and water react to form a solid that is too hard to pour.
C.The density of milk is exactly the same as water, making it float in the middle.
D.Milk particles are magnetic and stick to the water molecules.
- 9.
In the process of making coffee using a drip machine, what is the role of the paper filter?
A.To allow the dissolved coffee flavors (filtrate) to pass while keeping the grounds (residue) out.
B.To sieve the coffee beans into smaller pieces so they taste better.
C.To decant the hot water so it doesn't touch the coffee grounds for too long.
D.To act as a catalyst that changes the water into coffee chemically.
- 10.
A mixture contains three solids: Iron filings, Wood chips, and Salt. Which process would involve a phase change (change in state) to complete the separation of all three?
A.Decanting the wood chips from the water.
B.Filtering the iron filings.
C.Evaporating the water to recover the salt.
D.Sieving the wood chips from the iron filings.
Download the worksheet for Properties and Changes of Materials - Separating mixtures (filtering, sieving, and decanting) to practice offline. It includes additional chapter-level practice questions.
Conductivity and insulation of materials
SubtopicConductivity and insulation of materials under Properties and Changes of Materials for Grade 5 IGCSE.
Preview questions (no answers)
- 1.
Birds often fluff up their feathers in the winter. How does this help them?
A.It makes them look bigger to predators
B.It traps air, which is a good insulator, to keep them warm
C.It allows them to conduct more heat from the sun
D.It helps them fly faster in cold air
- 2.
Which of these would be the best material for making a protective case for a smartphone?
A.Aluminum
B.Silicone (Insulator)
C.Copper
D.Steel
- 3.
What is the result of placing a thermal insulator between a hot object and a cold object?
A.The hot object gets hotter
B.The cold object gets colder
C.The transfer of heat is slowed down
D.The heat is destroyed
- 4.
Why are the housings (outer shells) of many kitchen appliances like blenders made of plastic?
A.Plastic conducts electricity to the motor
B.Plastic is an electrical insulator, making it safe to touch
C.Plastic is a thermal conductor
D.Plastic is magnetic
- 5.
Why are many electrical components, like microchips, encased in plastic or ceramic?
A.To ensure they conduct electricity to everything nearby.
B.To insulate them and prevent unwanted electrical connections.
C.To help them heat up as much as possible.
D.To make them look more colorful and attractive.
- 6.
If you are stir-frying vegetables in a very hot wok, why would a wooden spatula be better than a metal one?
A.The wooden spatula will conduct heat faster to your hand.
B.The wooden spatula is a thermal insulator and won't get too hot to hold.
C.The metal spatula is a better insulator than the wooden one.
D.Wood is a better conductor of heat than metal.
- 7.
Which material is most likely used for the heating element inside a toaster because it conducts electricity and gets hot?
A.Plastic
B.Nichrome (a metal alloy)
C.Rubber
D.Glass
- 8.
When building a circuit to test if a material is a conductor, why should you briefly touch the two crocodile clips together before testing the material?
A.To charge up the clips.
B.To ensure the battery and bulb are working correctly (control check).
C.To clean the clips of any dirt.
D.To make the battery last longer.
- 9.
How does the molecular structure of an insulator like glass differ from a conductor like copper in terms of heat transfer?
A.In glass, molecules are free to move throughout the material.
B.In copper, there are free electrons that can move and transfer energy, while in glass, electrons are tightly bound.
C.Glass molecules are much larger and cannot vibrate.
D.Copper is a solid and glass is a liquid, so heat moves differently.
- 10.
Which of these experimental errors would most likely lead to a false conclusion about which material is the best electrical conductor?
A.Using the same battery for all tests.
B.Having different lengths of the materials being tested.
C.Using a bulb that is known to be working.
D.Testing all materials at room temperature.
Download the worksheet for Properties and Changes of Materials - Conductivity and insulation of materials to practice offline. It includes additional chapter-level practice questions.