Properties of Matter Flashcards
Heat is
a form of energy
Temperature is
a measure of the
mean (average) kinetic energy of its particles.
The unit of heat (energy) is
joules
or
J
The unit of specific heat capacity is
joules per kilogram per degree celsius
or
J kg-1Β°C-1
Specific heat capacity is
the energy required to increase the temperature of one kilogram of a material by one degree celsius
or
the energy released when the temperature of one kilogram of a material decreases by one degree celsius
The relationship between energy, specific heat
capacity, mass and temperature change is
energy = s.h.c Γ mass Γ temperature change
or
πΈβ= ππβT
The energy required to change the temperature of
a material depends on:
what itβs made from/its specific heat capacity
its mass the temperature increase
Heat can be transferred by three processes:
conduction
convection
radiation
The main method of heat transfer in solids is
conduction
The main method of heat transfer in fluids (liquids
and gases) is
convection
The only method of heat transfer in a vacuum is
radiation
The surfaces that radiate the most heat are
black
Specific latent heat of fusion is
the energy required to change one kilogram of a substance from a solid at its melting point to a liquid at the same temperature
or
the energy released when one kilogram of a
substance changes from a liquid at its freezing point to a solid at the same temperature
Specific latent heat of vaporisation is
the energy required to change one kilogram of a substance from a liquid at its boiling point to a gas at the same temperature
or
the energy released when one kilogram of a
substance changes from a gas at its condensation point to a liquid at the same temperature
The relationship between energy, specific latent
heat and mass is
energy = mass Γ specific latent heat
or
πΈβ= πl
While a material changes state its temperature
does not change
or
remains constant
The unit of latent heat are
joules per kilogram
or
J kg-1
Pressure is
force per unit area
The relationship between pressure, force and area is
F
p + β
A
The unit of pressure is
newtons per square metre or N m-2
or
pascals or Pa
The lowest possible temperature is known as
absolute zero
To unit of absolute temperature is
kelvin or K
To convert a temperature from degrees celsius to kelvin
add 273
Absolute zero is
0 K or -273 Β°C
The relationship between pressure and volume of a fixed mass of gas at constant temperature is
pressure is inversely proportional to volume
or
1
π β β
π
or
π1π1 = π2π2
The relationship between pressure and
temperature of a fixed mass of gas at constant volume is
pressure is directly proportional to temperature in
kelvin
or
π β π
or
π1 π2
β = β
π1 π2
The relationship between volume and temperature of a fixed mass of gas at constant pressure is
volume is directly proportional to temperature in
kelvin
or
π β π
or
π1 π2
β = β
π1 π2
The relationship between pressure, volume and temperature of a fixed mass of gas is
ππ
β = ππππ π‘πππ‘
π
or
π1π1 π2π2
ββ- = ββ-
π1 π2
In the kinetic model, gas particles are
in constant random motion
In the kinetic model, the pressure of a gas can be
accounted for by
the collisions of gas particles with the walls of the
container
When a gas is heated the particles move
faster
When the temperature of a gas increases the gas particles collide with the walls of the container
with more force (harder) and more frequently
When the volume of a container is decreased the particles collide with the walls of the container
with the same force, but more frequently
When the temperature of a gas decreases the gas particles collide with the walls of the container
with less force(less hard) and less frequently
When the volume of a container is increased the particles collide with the walls of the container
with the same force, but less frequently
Using Kinetic Theory explain what happens to the pressure if you increase the temperature of a fixed mass gas in a fixed volume container?
Pressure is caused by the force of particles hitting the sides of the container.
The temperature is increased. The particles gain kinetic energy.
They will move faster and so hit the sides of the container more often and with a greater velocity and so greater force.
So the pressure increases.
Using Kinetic Theory explain what happens to the pressure if you decrease the volume of a fixed mass gas at a constant temperature?
Pressure is caused by the force of particles hitting the sides of the container.
The volume is decreased. The particles have less room to move about and so hit the sides of the container more often creating a larger force.
So the pressure increases.
Describe an experiment to investigate the relationship between the pressure and the volume of a fixed mass of gas, at a constant temperature.
Boyles Law:
A pump is used to put pressure on oil which puts pressure on a fixed mass of trapped gas.
Valve is closed.
Volume of air column is read off the scale.
Pressure is read off the bourdon gauge.
Valve is opened and closed to change the pressure to get a set of readings.
Draw graph of pressure against volume.
What is conservation of energy?
Energy cannot be created or destroyed it can only be transferred from one type to another.
Explain how snow shoes prevent you sinking into the snow.
Snow shoes have a large area. So the force of the person (weight) is spread over a larger area so the pressure exterted on the snow is less as P = F/A
