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Matter and Materials
States of matter, properties and changes
Class VI
Science
9 Questions
MCQ
1 marks
Which of the following is NOT a state of matter?
Options:
a) Solid
b) Liquid
c) Gas
d) Energy
Answer:
Energy is not a state of matter. The three main states of matter are solid, liquid, and gas.
MCQ
1 marks
What happens to water when it is heated to 100°C?
Options:
a) It freezes
b) It evaporates
c) It expands
d) It contracts
Answer:
Water evaporates (turns into water vapor/gas) when heated to its boiling point of 100°C.
MCQ
1 marks
Which property helps us identify different materials?
Options:
a) Color only
b) Size only
c) Color, texture, hardness
d) Weight only
Answer:
Materials can be identified by multiple properties including color, texture, hardness, density, etc.
SHORT
2 marks
List the three states of matter with one example each.
Answer:
Three states of matter: 1. Solid - Example: Ice, wood, stone 2. Liquid - Example: Water, milk, oil 3. Gas - Example: Air, steam, oxygen Solids have fixed shape and volume, liquids have fixed volume but no fixed shape, gases have neither fixed shape nor volume.
SHORT
2 marks
What is the difference between melting and freezing?
Answer:
Melting: Process where solid changes to liquid when heated (ice to water) Freezing: Process where liquid changes to solid when cooled (water to ice) Melting and freezing are opposite processes that occur at the same temperature called the melting/freezing point.
SHORT
2 marks
Name five properties of materials that help us classify them.
Answer:
Five properties of materials: 1. Hardness - How difficult it is to scratch 2. Transparency - Can light pass through it 3. Solubility - Does it dissolve in water 4. Density - How heavy it is for its size 5. Conductivity - Does it allow heat/electricity to pass through
LONG
5 marks
Explain the changes of state with examples and the role of temperature.
Answer:
Changes of State: 1. Melting (Solid → Liquid): • Example: Ice melts to water when heated • Temperature increases 2. Freezing (Liquid → Solid): • Example: Water freezes to ice when cooled • Temperature decreases 3. Evaporation (Liquid → Gas): • Example: Water evaporates to steam when heated • Can happen at any temperature 4. Condensation (Gas → Liquid): • Example: Steam condenses to water when cooled • Temperature decreases 5. Sublimation (Solid → Gas): • Example: Dry ice directly becomes gas • Skips liquid state Role of Temperature: • Heating provides energy for particles to move faster • Cooling removes energy, particles move slower • Each material has specific temperatures for state changes
LONG
5 marks
Classify the following materials as natural or artificial and explain their uses: Wood, Plastic, Cotton, Steel, Rubber.
Answer:
Classification of Materials: NATURAL MATERIALS: 1. Wood: • Source: Trees • Uses: Furniture, construction, paper, fuel • Properties: Hard, can be shaped, burns 2. Cotton: • Source: Cotton plant • Uses: Clothing, bed sheets, bandages • Properties: Soft, absorbent, breathable ARTIFICIAL MATERIALS: 1. Plastic: • Source: Made from petroleum/chemicals • Uses: Bottles, bags, toys, containers • Properties: Light, waterproof, durable 2. Steel: • Source: Made from iron and carbon • Uses: Buildings, vehicles, tools, utensils • Properties: Very hard, strong, magnetic 3. Rubber: • Source: Can be natural (rubber tree) or synthetic • Uses: Tires, shoes, erasers, gloves • Properties: Elastic, waterproof, flexible Artificial materials are often designed to have specific properties that make them useful for particular purposes.
LONG
5 marks
Describe an experiment to show that air occupies space and has weight.
Answer:
Experiment to Show Air Occupies Space: Materials needed: • Empty bottle • Water • Large bowl Procedure: 1. Fill a large bowl with water 2. Turn an empty bottle upside down 3. Push the bottle straight down into water 4. Observe that water does not enter the bottle completely Observation: Water cannot enter the bottle because air inside occupies space and prevents water from entering. Experiment to Show Air Has Weight: Materials needed: • Balance scale • Two balloons • Pump Procedure: 1. Place two uninflated balloons on either side of balance 2. Balance them so they weigh the same 3. Inflate one balloon with air 4. Place it back on the balance Observation: The inflated balloon side goes down, showing that air has weight. Conclusion: These experiments prove that air is matter because it occupies space and has weight, even though we cannot see it.