P3 The Particle Model Of Matter Flashcards
What is density?
The mass of a substance per unit volume
What is the unit of mass?
kg
What is the unit of volume?
m^3
Explain density in a solid:
More particles in the same unit of volume
Explain density in a liquid:
Slightly less particles in the same unit of volume
Explain density in a gas:
Few particles in the same unit of volume
What is the equation for density?
Density = mass / volume
Describe the particle arrangement in a solid:
Particles arranged regularly in rows, all in contact, same size particles
Describe the particle arrangement in a liquid:
Particles irregularly arranged, mostly still in contact, same size particles
Describe the particle arrangement in a gas:
Particles free to move, not touching or arranged in any way, same size particles
How does length of wire impact resistance?
As the length of the wire increases, the resistance of the wire also increases - directly proportional relationship
What is the independent variable?
What we change
What is the dependent variable?
What we measure
What is the control variable?
What we keep the same
Do solids have a high/low potential energy store?
Higher potential energy store than gases
What forces of attraction act on solids?
Strong intermolecular forces of attraction
Do gases have a high/low potential energy store?
Lower potential energy store than gases
What forces of attraction act of gases?
No intermolecular forces of attraction
What is the name of the transfer gas to liquid?
Condensing
What is the name of the transfer liquid to solid?
Freezing
What is the name of the transfer solid to gas?
Sublimation
What is the name of the transfer solid to liquid?
Melting
What is the name of the transfer liquid to gas?
Boiling
What happens when particles go solid to liquid and liquid to gas?
Particles gain energy to overcome the intermolecular forces of attraction. This energy is stored in the particle’s energy store
What happens when particles go gas to liquid and liquid to solid?
Particles lose energy as solids and liquids have a higher potential energy store
What is the specific latent heat of fusion?
The energy required to convert 1kg of a solid to liquid (or from a liquid to solid) without a change in temperature
What is the specific latent heat of vapourisation?
The energy required to convert 1kg of a substance from a liquid to a gas (or from a gas to a liquid) without a change in temperature
What is the equation for specific latent heat?
Latent heat = Energy / mass
What is the unit of pressure?
Pascals, Pa
What is the equation for the gas constant?
P x V = Constant
What is pressure in gases caused by?
Particles hitting the surface
What is specific heat capacity?
Energy needed to heat 1kg by 1 degree celsius
Why does dry ice explode?
Particles gain energy, move faster, hit sides more, changes solid to gas (sublimation)
What shape do gases take when compressed?
The shape of the container they are in
Which states can be compressed?
Only gases
Which states can’t be compressed?
Liquids and solids
When do state changes occur?
When particles gain or lose energy
What temperatures do gases contract at?
Lower temperatures - slow down and get closer
What are particles?
Atoms and molecules
What do higher temperatures mean for movement of particles?
Higher temperatures = more movement (speeds up)
What do lower temperatures mean for movement of particles?
Lower temperatures = less movement (slows down)
Which state particles have the weakest forces of attraction?
Particles in gases have the weakest forces of attraction
How is atmospheric pressure affected by height?
Atmospheric pressure decreases the higher you travel
What happens when a substance melts or boils?
When the substance melts or boils, energy is put in to breaking the bonds that are holding particles together, which increases the potential energy.
What is internal energy?
The total kinetic and potential energy of the particles in an object
What happens when energy is given to raise the temperature?
When energy is given to raise the temperature, particles speed up and gain kinetic energy.
