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Worksheet StudioPractice pack · Ages 10-12
Solids, liquids & gases
Take your time. Show your thinking.
1. Why does the smell of baking bread spread across a quiet room even without wind: diffusion (random particle motion from high to low concentration), or gravity?
Solid → Liquid → Gas · Particle Arrangement
2. Does the total mass of an ice cube change when it melts completely in a sealed cup: No (mass is conserved) or Yes (it doubles)?
Solid → Liquid → Gas · Particle Arrangement
3. What is the change of state when water vapour cools on a cold mirror and forms liquid droplets: condensation or melting?
Solid → Liquid → Gas · Particle Arrangement
4. At standard atmospheric pressure, at what temperature does pure liquid water boil into steam: 100 °C or 50 °C?
Solid → Liquid → Gas · Particle Arrangement
5. Why does water expand slightly when it freezes into ice (making ice float on liquid water): water molecules form an open hexagonal crystal lattice, or ice gains extra atoms?
Solid → Liquid → Gas · Particle Arrangement
6. What is the key difference between boiling and evaporation: boiling happens throughout the liquid at its boiling point, whereas evaporation happens at the surface at any temperature, or they are identical?
Solid → Liquid → Gas · Particle Arrangement
7. Which state of matter spreads out to fill the entire volume and shape of any closed container: gas or solid?
Solid → Liquid → Gas · Particle Arrangement
8. While pure ice is melting at 0 °C, what happens to its temperature until all the ice has melted: the temperature stays constant at 0 °C, or it jumps to 100 °C?
Solid → Liquid → Gas · Particle Arrangement
9. What is the change of state from a liquid to a solid when cooled: freezing (solidification) or evaporation?
Solid → Liquid → Gas · Particle Arrangement
10. In which state of matter can a substance be easily compressed into a much smaller volume (such as air in a bicycle pump): gas or liquid?
Solid → Liquid → Gas · Particle Arrangement
11. Which metallic element is unusual because it is a liquid at standard room temperature (20 °C): mercury or iron?
Solid → Liquid → Gas · Particle Arrangement
12. When a solid dissolves in a liquid (such as salt in water), is the change physical and reversible by evaporation, or does it destroy the salt?
Solid → Liquid → Gas · Particle Arrangement
12 questions · Seed 42 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 10-12
Solids, liquids & gases
Answers and reasoning. Review before teaching.
1. Why does the smell of baking bread spread across a quiet room even without wind: diffusion (random particle motion from high to low concentration), or gravity?
Diffusion (random particle motion from high to low concentration)
Gas molecules move randomly and spread from higher concentration to lower concentration by diffusion.
2. Does the total mass of an ice cube change when it melts completely in a sealed cup: No (mass is conserved) or Yes (it doubles)?
No (mass is conserved)
The same number of water molecules are present before and after melting, so mass is conserved.
3. What is the change of state when water vapour cools on a cold mirror and forms liquid droplets: condensation or melting?
Condensation
Condensation is the transition from gas (vapour) to liquid when cooled.
4. At standard atmospheric pressure, at what temperature does pure liquid water boil into steam: 100 °C or 50 °C?
100 °C
The normal boiling point of pure water is 100 °C.
5. Why does water expand slightly when it freezes into ice (making ice float on liquid water): water molecules form an open hexagonal crystal lattice, or ice gains extra atoms?
Water molecules form an open hexagonal crystal lattice
Hydrogen bonding in ice holds molecules slightly farther apart than in cold liquid water, lowering its density.
6. What is the key difference between boiling and evaporation: boiling happens throughout the liquid at its boiling point, whereas evaporation happens at the surface at any temperature, or they are identical?
Boiling happens throughout the liquid at its boiling point, whereas evaporation happens at the surface at any temperature
Evaporation is a surface process below the boiling point; boiling forms vapour bubbles throughout the bulk liquid.
7. Which state of matter spreads out to fill the entire volume and shape of any closed container: gas or solid?
Gas
Gas particles are far apart and move rapidly in all directions.
8. While pure ice is melting at 0 °C, what happens to its temperature until all the ice has melted: the temperature stays constant at 0 °C, or it jumps to 100 °C?
The temperature stays constant at 0 °C
Supplied thermal energy (latent heat of fusion) goes into breaking intermolecular bonds rather than raising temperature.
9. What is the change of state from a liquid to a solid when cooled: freezing (solidification) or evaporation?
Freezing (solidification)
Cooling removes thermal energy until liquid particles lock into a solid structure.
10. In which state of matter can a substance be easily compressed into a much smaller volume (such as air in a bicycle pump): gas or liquid?
Gas
Because gas particles have large empty spaces between them, gases are easily compressed.
11. Which metallic element is unusual because it is a liquid at standard room temperature (20 °C): mercury or iron?
Mercury
Mercury melts at −38.8 °C, so it is liquid at room temperature.
12. When a solid dissolves in a liquid (such as salt in water), is the change physical and reversible by evaporation, or does it destroy the salt?
Physical and reversible by evaporation
Evaporating the water leaves the solid salt crystals behind.
12 questions · Seed 42 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 10-12
Solids, liquids & gases
Take your time. Show your thinking.
1. Why does the smell of baking bread spread across a quiet room even without wind: diffusion (random particle motion from high to low concentration), or gravity?
Solid → Liquid → Gas · Particle Arrangement
2. Does the total mass of an ice cube change when it melts completely in a sealed cup: No (mass is conserved) or Yes (it doubles)?
Solid → Liquid → Gas · Particle Arrangement
3. What is the change of state when water vapour cools on a cold mirror and forms liquid droplets: condensation or melting?
Solid → Liquid → Gas · Particle Arrangement
4. At standard atmospheric pressure, at what temperature does pure liquid water boil into steam: 100 °C or 50 °C?
Solid → Liquid → Gas · Particle Arrangement
5. Why does water expand slightly when it freezes into ice (making ice float on liquid water): water molecules form an open hexagonal crystal lattice, or ice gains extra atoms?
Solid → Liquid → Gas · Particle Arrangement
6. What is the key difference between boiling and evaporation: boiling happens throughout the liquid at its boiling point, whereas evaporation happens at the surface at any temperature, or they are identical?
Solid → Liquid → Gas · Particle Arrangement
7. Which state of matter spreads out to fill the entire volume and shape of any closed container: gas or solid?
Solid → Liquid → Gas · Particle Arrangement
8. While pure ice is melting at 0 °C, what happens to its temperature until all the ice has melted: the temperature stays constant at 0 °C, or it jumps to 100 °C?
Solid → Liquid → Gas · Particle Arrangement
9. What is the change of state from a liquid to a solid when cooled: freezing (solidification) or evaporation?
Solid → Liquid → Gas · Particle Arrangement
10. In which state of matter can a substance be easily compressed into a much smaller volume (such as air in a bicycle pump): gas or liquid?
Solid → Liquid → Gas · Particle Arrangement
11. Which metallic element is unusual because it is a liquid at standard room temperature (20 °C): mercury or iron?
Solid → Liquid → Gas · Particle Arrangement
12. When a solid dissolves in a liquid (such as salt in water), is the change physical and reversible by evaporation, or does it destroy the salt?
Solid → Liquid → Gas · Particle Arrangement
12 questions · Seed 42 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 10-12
Solids, liquids & gases
Answers and reasoning. Review before teaching.
1. Why does the smell of baking bread spread across a quiet room even without wind: diffusion (random particle motion from high to low concentration), or gravity?
Diffusion (random particle motion from high to low concentration)
Gas molecules move randomly and spread from higher concentration to lower concentration by diffusion.
2. Does the total mass of an ice cube change when it melts completely in a sealed cup: No (mass is conserved) or Yes (it doubles)?
No (mass is conserved)
The same number of water molecules are present before and after melting, so mass is conserved.
3. What is the change of state when water vapour cools on a cold mirror and forms liquid droplets: condensation or melting?
Condensation
Condensation is the transition from gas (vapour) to liquid when cooled.
4. At standard atmospheric pressure, at what temperature does pure liquid water boil into steam: 100 °C or 50 °C?
100 °C
The normal boiling point of pure water is 100 °C.
5. Why does water expand slightly when it freezes into ice (making ice float on liquid water): water molecules form an open hexagonal crystal lattice, or ice gains extra atoms?
Water molecules form an open hexagonal crystal lattice
Hydrogen bonding in ice holds molecules slightly farther apart than in cold liquid water, lowering its density.
6. What is the key difference between boiling and evaporation: boiling happens throughout the liquid at its boiling point, whereas evaporation happens at the surface at any temperature, or they are identical?
Boiling happens throughout the liquid at its boiling point, whereas evaporation happens at the surface at any temperature
Evaporation is a surface process below the boiling point; boiling forms vapour bubbles throughout the bulk liquid.
7. Which state of matter spreads out to fill the entire volume and shape of any closed container: gas or solid?
Gas
Gas particles are far apart and move rapidly in all directions.
8. While pure ice is melting at 0 °C, what happens to its temperature until all the ice has melted: the temperature stays constant at 0 °C, or it jumps to 100 °C?
The temperature stays constant at 0 °C
Supplied thermal energy (latent heat of fusion) goes into breaking intermolecular bonds rather than raising temperature.
9. What is the change of state from a liquid to a solid when cooled: freezing (solidification) or evaporation?
Freezing (solidification)
Cooling removes thermal energy until liquid particles lock into a solid structure.
10. In which state of matter can a substance be easily compressed into a much smaller volume (such as air in a bicycle pump): gas or liquid?
Gas
Because gas particles have large empty spaces between them, gases are easily compressed.
11. Which metallic element is unusual because it is a liquid at standard room temperature (20 °C): mercury or iron?
Mercury
Mercury melts at −38.8 °C, so it is liquid at room temperature.
12. When a solid dissolves in a liquid (such as salt in water), is the change physical and reversible by evaporation, or does it destroy the salt?
Physical and reversible by evaporation
Evaporating the water leaves the solid salt crystals behind.
12 questions · Seed 42 · Age guidance, not curriculum certification