Kinetic Particle Model of Matter

Question 1

Describe the Kinetic Particle Model of a Matter

Answer 1

The model that explains the properties of the different states of matter, the particles in solids, liquids and gases have different amounts of energy, are arranged differently and move in different ways.

Question 2

Name the three assumptions of the kinetic particle model

Answer 2

1. All matter is made up of small particles in constant motion; they have kinetic energy
2. Collisions between particles are perfectly elastic; the total kinetic energy before and after the collision is the same
3. The particles obey classical mechanics and only interact with each other when they collide

Question 3

What is thermal energy?

Answer 3

Thermal energy refers to the energy contained within a system that is responsible for its temperature.

Question 4

What is internal energy?

Answer 4

The internal energy (U also thermal energy) of a substance is the sum of the kinetic energy of its particles and the potential energy stored in their bonds.

Question 5

What is kinetic energy?

Answer 5

The energy of an object due to its motion

Question 6

What is temperature?

Answer 6

a measurement of the average kinetic energy of the particles in a substance

Question 7

What is conduction?

Answer 7

Conduction is the transfer of heat energy through a substance by the action of particle collisions. When two substances of different temperatures are placed in contact with each other, the particles of the hotter substance collide with those in the colder substance and transfer kinetic energy.

Question 8

What happens to the substance in the transfer of heat in conduction?

Answer 8

This transfer of heat results in a decrease of the total kinetic energy of the hotter substance and an increase in the overall kinetic energy of the colder substance.

Question 9

What is convection?

Answer 9

Convection is the transfer of heat energy by the bulk movement of particles. The flow of particles away from a warmer to a cooler region produces a convection current. These currents result in a net flow of heat away from the warmer region to the colder region.

Question 10

Where do convection currents occur?

Answer 10

Convection currents only occur in liquids and gases, which have relatively weakly connected particles, more in gases for this reason.

Question 11

How is a convection cell produced?

Answer 11

Warm, less dense water is at the bottom flows upwards while less dense at the water sinks. A convection cell is produced.

Question 12

What is radiation?

Answer 12

Radiation is the transfer of energy that does not need a medium. Unlike conduction and convection, radiation does not involve particles of matter. Except at 0K, all objects emit electromagnetic radiation.

Question 13

What happens when radiated energy interacts with an object?

Answer 13

When radiated energy (radiant heat) interacts with an object, some of that energy is absorbed and the rest is reflected.
The fraction that is absorbed depends on the type of surface material, its texture and its colour.

Black and dark-coloured surfaces absorb more radiant heat than white or light-coloured surfaces. Hence a black car gets hotter inside than white or light-coloured surfaces. Hence a black car gets hotter inside than a white car on a sunny day.

Question 14

What happens in an elastic collison?

Answer 14

In an elastic collision kinetic energy is conserved. Kinetic energy is transferred from one particle to another, but not converted into potential energy.

Question 15

KEY FORMULA: kinetic particle model

Answer 15

This model of gas is the kinetic particle or ideal gas model, when these assumptions are made the gas is an ideal gas. In this instance, it can be shown that the average kinetic energy of the particles in an ideal gas is directly proportional to the temperature of the gas.

Question 16

What does the ideal gas equation state?

Answer 16

The ideal gas equation states that the faster the particles of a gas are moving, the higher the temperature of the gas. This equation is correct for ideal gases, however the last assumption is not correct as the particles in a substance interact even when they are not in the process of colliding. In all known substances, there is some degree of attraction between the particles within them.

Question 17

How are particles attracted to each other in the ideal gas equation?

Answer 17

The particles are attracted to each other by intermolecular forces that bind them together and cause them to behave a bit like springs. There is an ideal length for any bond, but it is possible for the bond to be stretched and compressed. When this bond is stretched away from its ideal length by the movement of particles, the energy can be stored as elastic potential energy.

Question 18

How is a substance found in a particular state of matter?

Answer 18

It is the balance achieved between the kinetic energy given to the particles because of the temperature of the substance and the strength of the intramolecular bonds that cause a substance to be found in a particular state of matter.

Question 19

What are the qualities of gas? (4)

Answer 19

• Higher temp than solid and liquid states
• Average kinetic energy of atoms/molecules large enough to break free from bonds that hold them together
• Particles free to move in any direction and only interact through elastic collisions
• When they do collide, the force of attraction is too small to keep them together

Question 20

What are the qualities of liquids (1)?

Answer 20

-Particles have less kinetic energy so the bonds begin to have an effect, but they still only loosely bind the particles together. There is potential energy in the interactions between particles causing them to stay together, but they have enough kinetic energy so that they can slide over each other.

Question 21

Qualities of solids (2)

Answer 21

• Kinetic energy low, intramolecular forces keep the particles bound together as a cohesive whole
• Material may not be going anywhere, every atom or molecule still moving constantly, vibrating or oscillating about its relative fixed position

Question 22

What are bosons?

Answer 22

When these particles approached absolute zero, they would all “condense” down into a form in which all atoms began occupying the same identical quantum state. They had effectively predicted a new physical state of matter. These particles do not obey the exclusion principle.

Question 23

What is the plank radiation curve?

Answer 23

Plank Radiation Curve: a formula that describes the relationship between the electromagnetic radiation emitted by a substance and its temperature . Any object with a temperature greater than absolute zero will emit electromagnetic radiation.
All matter emits radiation

Question 24

What is the energy model?

Answer 24

All forms of energy can be transformed from one form to another and transferred from one place to another. SI unit of Joules (J)

Question 25

Kinetic energy in the Kinetic Particle model

Answer 25

In the Kinetic Particle Model each atom/molecule in a substance has kinetic energy due to the random velocity that it has at any one time. It is important to remember that there is a range of kinetic energies that the particles may have but that an average kinetic energy may be calculated.

The conservation of kinetic energy in an elastic collision:
Ek initial = Ek final Delta Ek=0

Question 26

What happens to the temperature and particles when a solid body is heated?

Answer 26

If a solid body is heated, its temperature increases. The particles gain kinetic energy, and on average vibrate faster. Therefore, as temperature increases, the amount of internal energy increases as well.

Question 27

What happens to the temperature and particles when a solid body is melted?

Answer 27

At melting point, there is a phase change. The kinetic energy of the particles doesn’t change until the phase change is complete. The “springs” are affected and the particles become further separated. During the phase change, the energy input is used to increase the distance between particles, not their kinetic energy. In this case when energy is added to a substance undergoing a phase change, even though there is no increase in temperature (no increase in kinetic energy), the internal energy is still increasing because more potential energy is being stored in its bonds.

Question 28

What happens when a material is heated, boltzmann distribution?

Answer 28

When a material is heated, the average kinetic energy of the particle increases. The Boltzmann distribution shows the wide range of kinetic energies of particles in the same mass of iron and at two different temperatures. The peak of the curve is the most common (mode) kinetic energy of the particles.

Question 29

What happens when energy is added to a substance?

Answer 29

When energy is added to a substance, the proportion of atoms vibrating faster increases. The average kinetic energy of the particles increases, and therefore the temperature increases.

Question 30

What happens to the particles when temperature is lowered in a material?

Answer 30

The lower the temperature, the more likely it is for the particles to have the same kinetic energy. More particles in lower temperatures are most likely to have the same kinetic energy, however, higher temp particles are more unpredictable. `

Question 31

Heat and thermal energy

Answer 31

Heat or thermal energy refers to energy that spontaneously moves between two substances because there is a difference in temperature between them.

When heat is added, increases kinetic energy, increases the temperature.
Heat refers to the energy that is actually being transferred, not the kinetic energy itself.

Question 32

Different materials have different conducting properties

Answer 32

Different Materials have different conducting properties.
Thermal conductivity is a measure of how efficiently heat will flow through a substance. Solids are better heat conductors than liquids or gases. Heat insulators are poor heat conductors.

Question 33

Open system

Answer 33

energy and matter can flow freely into and out of the system

Question 34

Closed system

Answer 34

energy can flow freely into and out of the system, but matter is contained

Question 35

Isolated system

Answer 35

energy and matter are contained within the system

Question 36

what does phase mean?

Answer 36

Phase – similar to state, and are often used interchangeably… technically “States of matter are the physical form taken by phases of matter.”

importantly, a phase of matter is uniform in its physical and chemical properties. So the state of water in a glass at 300 K is the liquid phase. But, the state of water at 273.15 K could be in solid or liquid phases