P1-Topic 3- Particle model of matter 2022 Flashcards
based on 2022 advanced info
What is the definition of density?
State the relevant equation with units
● The mass per unit volume of a material
● ⍴=m/v
● Density (kg/m³), Mass (kg), Volume (m³)
State the different states of matter in order (least to
most) of density of atoms
● Least dense: Gas
● Liquid
● Most dense: Solid
Describe the particle arrangement of a solid.
2
Tightly packed in a regular arrangement.
Particles can only vibrate on the spot
Describe the particle arrangement of a liquid 2
Close together, but with an irregular arrangement.
They can flow over each
other
Describe the particle arrangement of a gas.2
Separated, with no regular arrangement.
Particles can move freely
What is always conserved when a substance undergoes a change of state?
Mass
How does a change of state differ from a chemical change? 2
In a change of state, the material can return to having its previous properties if the change is reversed
-this means that changes of state are physical changes not chemical
What is sublimation?
When a solid changes into a gas without passing through a liquid state
What is evaporation?
When a liquid changes into a gas state
When water boils in an open pan, why does the mass of the pan of water appear to decrease?
Some of the water will evaporate and turn
into water vapour.
This will leave the pan
meaning the mass of the pan will decrease.
The mass of the whole system however
remains constant.
Explain the processes involved when a bathroom mirror mists up
● Hot water evaporates to form water vapour
● This water vapour lands on the cooler mirror
● The vapour condenses and returns to liquid
state on the mirror’s surface
What is the internal energy of a substance?2
● The energy stored by the particles
● The sum of the total kinetic and potential energies that make up the system
How does heating affect the energy of a substance?
● Heating transfers energy to the substance
● It increases the energy of the particles that make up the substance
What two things can heating a substance
do?
- Raise its temperature
2. Change the state of the substance
What three factors determine the temperature change of a system?
- Mass of substance being heated
- Type of material (Specific heat
capacity) - Energy inputted into the system
State the equation used to calculate the
temperature change when a substance
is heated. Give appropriate units.
● ΔE = m c Δ𝛉
● Energy (J), Mass (kg), Specific Heat
Capacity (J/kg/°C), Temperature (°C)
Define specific heat capacity.
The amount of energy needed to
increase the temperature of 1kg of a
substance by 1°C
Describe how the internal energy and
temperature of a substance changes
when a change of state occurs 2
● The internal energy of the substance
will be increased or decreased
● The temperature of the substance will
remain constant
Define specific latent heat
The amount of energy needed to change
the state of 1kg of a substance with no
change in temperature
State the equation for the energy
required to change state. Give
appropriate units.
energy for a change of state = mass × specific latent heat
E = m L
energy, E, in joules, J
mass, m, in kilograms, kg
specific latent heat, L, in joules per kilogram, J/kg
What is the specific latent heat of fusion?
The energy required to change 1kg of a
substance from solid state to liquid state
without a change in temperature.
What is the specific latent heat of
vaporisation?
The energy required to change 1kg of a
substance from liquid state to gas state
(vapour) without a change in
temperature.
