Studied by 6 people
When the kinetic energy of the particles in a substance increases, what happens to the substance?
Temperature increases
When the pressure inside a closed container is much bigger than the pressure outside the container, what can happen?
Explosion
When the pressure outside an open container is bigger than the pressure inside, what happens?
Air moves into the container
Complete this sentence: Decreasing the temperature of a gas …............... the gas pressure.
decreases
What symbol is used instead of writing the word 'temperature'?
ϴ (the Greek letter theta)
What symbol is used instead of writing the words 'specific heat capacity'?
c
What piece of equipment is used to measure length?
ruler
In what case would an object lose heat to the surroundings?
When the surroundings are colder than the object.
Why do substances have different melting points?
Different forces between particles
Define the specific latent heat of vaporisation of a substance.
Amount of energy needed to boil 1 kg of the substance with no change in temperature
At what temperature do melting and freezing take place for water?
0 ᵒC
State the unit of temperature.
degrees Celcius or ᵒC
Which state of matter is usually the least dense?
gas
When particles move faster, their …........... energy increases.
kinetic
Describe the arrangement of particles in a liquid.
Closely packed, not regular arrangement
What causes gas pressure?
Collisions of particles
Why does ice melt faster when placed on most metals than on most non-metals?
Metals are better conductors of heat
in what case would an object absorb heat from the surroundings?
When the surroundings are hotter than the object.
What is volume?
The amount of space an object fills
Why do substances expand when heated?
The particles gain kinetic energy and move further apart
How can gas turn to liquid without increasing temperature?
Increasing pressure
What is a system?
A group of interacting parts
What happens to the density of a substance when it is heated and expands
Decreases
State the equation linking density, mass and volume.
Mass = density x volume
Which state(s) of matter can be compressed?
gas
Are changes of state physical or chemical changes?
physical
What name is given to the total kinetic and potential energy of all the particles in a system?
Internal energy
When the pressure inside an open container is bigger than the pressure outside, what happens?
Air moves out of the container
Why do liquids and gases take the shape of their container?
The particles can move around
What piece of equipment is used to measure the volume of a liquid?
Measuring cylinder
At what temperature do boiling and condensing take place for water?
100 ᵒC
When a force decreases the volume of a substance the substance has been …
Compressed
In the particle model of matter, what are 'particles'?
Atoms, molecules or ions
What name is given to the mass per unit volume of a material?
density
When particles move further apart, their …................ energy increases.
potential
What symbol is used instead of writing the word 'volume'?
V
Why don't solids take the shape of their container?
The particles can't move around
Name the state change: Solid to gas.
Sublimation
At what temperature do melting and freezing take place?
The melting point
Describe the forces between particles in a liquid.
Weaker than in a solid
Name the state change: Liquid to gas.
Boiling
How do you convert from cm³ to m³?
÷ 1,000,000
How do you convert from g into kg?
÷ 1000
On a cooling or heating curve, what is happening in the horizontal sections?
Change of state at constant temperature
Describe the motion of the particles in a gas.
Move freely and randomly with a range of speeds and directions
What symbol is used instead of writing the word 'density'?
ρ (the Greek letter rho)
At what temperature do boiling and condensing take place?
The boiling point
What piece of equipment is used to measure temperature?
Thermometer
Why is mass conserved during state changes?
No particles are added or taken away
Why can't liquids and solids be compressed?
There isn't space between the particles
Complete this sentence: Increasing the temperature of a gas …............... the gas pressure.
increases
The force exerted by particles in a gas colliding with each other and the walls of the container causes …
Gas pressure
Why are solids usually denser than liquids and gases?
More particles per unit volume
Why can't solids flow?
The forces between particles are too strong so the particles can't move around
What symbol is used instead of writing the word 'energy'?
E
Describe the arrangement of particles in a solid.
Closely packed, regular arrangement
Latent heat of vaporisation relates to which state change?
Liquid to gas OR boiling
What is evaporation?
The change from liquid to gas below the boiling point
In what 3 ways can gas pressure be increased?
Smaller volume, higher temperature, more particles
State the unit of density
kg/m³ or kilogram per cubic metre
Why are solids usually the best conductors of heat and electricity?
The particles are closely packed
What symbol is used instead of writing the word 'mass'?
m
Why does ice melt faster when placed on a surface which is a better conductor of heat?
Heat transfers to the ice faster
Which part of internal energy relates to changes of state?
Potential energy
Why can liquids and gases flow?
The forces between particles are weak enough for the particles to move around
What symbol is used instead of writing the word 'change'?
△ (the Greek letter delta)
Describe the forces between particles in a gas.
Almost zero
Name the state change: Liquid to solid.
Freezing
Describe the arrangement of particles in a gas.
Far apart
Which state of matter: Particles close together and can move over each other.
liquid
Explain why increasing the temperature of a gas increases the gas pressure.
Particles have more kinetic energy and move faster so collide more often with a greater force
What piece of equipment is used to measure mass?
Mass balance
Name the state change: Gas to liquid.
Condensing
On a cooling or heating curve, what is happening in the sloping sections?
Change of temperature
Which state of matter: Particles closely packed and vibrate on the spot.
Solid
Define the specific heat capacity of a substance.
Amount of energy needed to increase the temperature of 1 kg of the substance by 1 ᵒC
Why do hotter fluids rise above colder fluids?
Hotter fluids are less dense than colder fluids
Which state changes can occur when a substance is heated?
Melting and boiling
Latent heat of fusion relates to which state change?
Solid to liquid OR melting
Describe the forces between particles in a solid.
strong
Define the specific latent heat of fusion of a substance.
Amount of energy needed to melt 1 kg of the substance with no change in temperature
Name the state change: Solid to liquid.
Melting
Which state of matter is usually the most dense?
solid
Describe the motion and kinetic energy of the particles in a solid.
Vibrate about fixed positions, low kinetic energy
State the unit of energy.
joules OR J
Are changes of state reversible or irreversible?
Reversible
What is conserved during changes of state?
mass
State the equation linking density, mass and volume using symbols.
m = ρV
Why can gases be compressed?
There is space between the particles
Define internal energy
The total kinetic and potential energy of all the particles in a system
Which state changes can occur when a substance is cooled?
Condensing and freezing
When the pressure outside a closed container is much bigger than the pressure inside the container, what can happen?
Implosion/collapse
When a substance is heated and increases in temperature without changing state its particles gain …............... energy.
kinetic
Describe the motion and kinetic energy of the particles in a liquid.
Move around, higher kinetic energy than in a solid
Which state of matter is usually the best conductor of heat and electricity?
solid
Which state(s) of matter can flow?
Liquid and gas
How is density related to floating?
Less dense substances float on more dense substances
Describe the kinetic energy of the particles in a gas.
high
The energy needed to increase the temperature of 1 kg of a substance by 1 ᵒC is called the …
Specific heat capacity
Define density.
Mass per unit volume
Note 
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