Physics (Jones) Thermal Physics Flashcards
What is temperate measured in
Degrees Celsius’s
How do you calculate thermal energy
E = Mc change in temperature
What is the SI base unit for temperature
Kelvin K
What does T mean
Absolute temperature
What is ideal gases law
PV = nRT
T(temperature in kelvin)
What is the thermodynamic scale
A temperature scale based on fundamental thermodynamics laws
What is absolute zero equal to
0K
-273 °C
What happens at absolute zero
Particles in a substance stop moving
What is 0K equal to and what type of change do Kelvin and degrees Celsius have
0K =-273°C
Change of 1°C = 1K
What is true about water and ice
Water is less dense in solid state then liquid state
What is a kinetic model
Describes how all substances are made up of atoms or molecules are arranged differently depending on there phase and state
How are solid molecules arranged
The atoms or molecules are regularly arranged and parked closely together
What type of force do solids have
Strong electrostatic force of attraction between them
What type of positing do solids have
A fixed position
How do solid particles move
They vibrate
Why do solids have kinetic energy
They vibrate
Do solids have kinetic energy
Yes
Can solids move out of position
They also cannot move out of their position
How are liquids molecules or molecules arranged
Still very close together but less then solid in most cases
What is true about the amount of kinetic energy when comparing liquids and solids
Liquids have more kinetic energy than solids
What is special about liquids
They can change there shape
How do liquids move
They are free to move around
What is true about the position of liquids
No fixed position
What is true about the arrangement of gas atoms or molecules
Gas atoms or molecules They are further apart then liquids
What is true about the kinetic energy of gases
It is greater than liquids
Why do gases have the highest kinetic energy
Move around at high speeds in different directions
Move around at high speeds
How do gas particles move
With high and different speeds and different directions
What type of force do gases have
Negligible elastic forces of attraction between them
What is special case for gases molecules and electrostatic attraction
Unless they collide with each other or a wall they have negligible elastic forces
How do gas particles move around
Free to move past each other
Why are gases free to move
Because of weak electrostatic forces of attraction
Why do solids vibrate
Because of strong electrostatic forces of attraction
What did the braumania motion model explain
Explained that pollen grain and water molecules collisions were elastic and resulted a transfer of momentum from water molecules to pollen grains to move in hap-hazardous ways
What did Beaumont’s motion provide
First significant proof of the kinetic model
In Braumania motion what is the kinetic model
The idea that matter is made up of atoms and molecules and they have kinetic energy
What did the Braumania motion experiment involve
Microscope
Lamp
Smoke + smoke cell
Convex lens
What type of motion did the particles Braumania motion have
Random motion of a smoke particle showing how it moves linearly in between collisions with air molecules
Why were smoke particles used in Braumania motion
Particles of smoker are large enough to be visible under a microscope
How do the smoke and air molecules move in Braumania motion
Particles move around in a random way
Air molecules moved in a random motion
Why is random motion caused in Braumania motion
Because air molecules striking the smoke particles
What does this random motion mean for the air molecules and smoke molecules
Mean Kinetic energy of the air molecules are equal to the mean kinetic energy of smoke particles
What is true about the smoke particles and therefore true about air particles
The bigger a smoke/air particle the slower it moves
What affects density
Space between particles (atoms or molecules) a substance in different phase difference affects the density of the substance
What is true in general substances
It is most dense in its solid state and least dense in its gaseous state
What is the exception to this general rule
Solid water is less dense than liquid water
Why is this exception happen
Because the molecules are held slightly further apart then in water
What is internal energy
The sum of the randomly distributed kinetic and potential energies of atoms or molecules within the substance
Why are there potential energies
Due to intermolecular forces between the molecules
What can internal energy never be
0
Why is there kinetic energy in a substance
Due to heat and temperature
Why is there potential energies
Due to change of state
What type of energy do gases have and how much
Electrostatic potential energy is zero
Why is the electrostatic potential energy in gases
Because electrostatic forces between atoms or molecules are negligible
What type of forces do liquids have
Electrostatic forces between atoms and molecules
What type of electrostatic potential energy
A negative value
What does a negative electrostatic potential energy mean
The negative means energy must be supplied to break the atomic or molecular bond
What type of force is acting on solids
Very large Electrostatic forces between atoms or molecules
What type of electro static potential energy does
Potential energy has a large negative value
What order is a solid and how do you change it
Pattern ( do work to remove pattern)
What order is a liquid in
No pattern
What order is a gas in
No pattern
What arrangement is a solid in
Closely packed
What arrangement is a liquid in and how do you change it
Closely packed (do work to remove from pack)
What arrangement does gas have
Not packed
big gaps
What is the motion of a solid
Vibrate fixed position
What is the motion of a liquid
Move around the system
What is the motion of a gas
They move at random speeds
What is a system
A large number of particles that are cut off from their surroundings
What is the equation for specific heat capacity
Change in energy = mass x change in temperature x specific heat capacity
What is E in specific heat capacity
Change in energy (J)
What is M in the specific heat capacity equation
Mass (kg)
What is specific heat capacity
Energy required per unit mass to change temperature by 1 degree Celsius or 1K
How do you determine specific heat capacity of a metal
Measure:
Mass of the block on top balance
Initial temperature on the thermometer and maximum temperature
Change in temperature = max temperature-initial temperature
E=IVt
A joule meter in parallel with the heater to measure the energy supplied Improve accuracy
How to improve the accuracy of the specific heat capacity experiment
Insulation
Keep temperature rise reasonable
What is specific latent heat
The energy required to change the store of 1kg of a substance
What is latent heat fusion
The latent heat that represents the change from solid to liquid
What is latenet heat vaporisation
The latent heat that represents the change from liquid to gas
What is the equation for specific latent heat
M = mass(kg)
L = latent heat
E = energy required
