Temperature And Phases Of Matter

Question 1

Temperature and pressure are

Answer 1

Proportional

Question 2

By changing temperature and pressure it is possible to get solid, liquid and gas at the same time. This is called the….

Answer 2

Triple point

Question 3

A phase diagram has … on the y axis and … on the x axis

Answer 3

Pressure against temperature

Question 4

By increasing the pressure of water you can

Answer 4

Get from water vapour to water provided that temperature is greater or equal to waters triple point

Question 5

What’s water triple point

Answer 5

0.01•C at a pressure of 0.61kPa

Question 6

Temperature is

Answer 6

A measure of how things are hot or cold

Question 7

How hot or cold an object is related to

Answer 7

Kinetic energy

Question 8

What are the 2 points that the Absolute scale is based on

Answer 8

Absolute zero and the triple point of water because both of these fixed no matter where you are in the universe

Question 9

What’s the triple point of water in degrees

Answer 9

0.01•C

Question 10

What’s the triple point of water in kelvin

Answer 10

273.16K

Question 11

Define heating

Answer 11

The transfer of energy from a region of higher temperature to one at a lower temperature.

Question 12

Object A has a higher temperature than object B. Object A and object B are touching. Describe the way object B is heated.

Answer 12

Object B is heated by object A. Object A is heating object B

Question 13

If body A is in thermal equilibrium with body B and body B is also in thermal equilibrium with body C. Then…

Answer 13

Body A and body C must be in thermal equilibrium with each other and all the bodies will have the same temperature

Question 14

The phases of matter are

Answer 14

Solid
Liquid
Gas

Question 15

What are the two points that the degree Celsius is based on

Answer 15

The freezing point of water and the boiling point of water at 1 atmospheric pressure

Question 16

Define the triple point

Answer 16

A specific temperature and pressure where the 3 phases of matter can exist in thermal equilibrium.

Question 17

The kinetic model describes

Answer 17

How all substances are made up of atoms or molecules. Which are arranged differently depending non the phase of the substance

Question 18

Using the kinetic model, how are atoms or molecules are arranged in solids

Answer 18

In solids the atoms or molecules are regularly arranged and packed closely together with strong electrostatic forces of attraction between them holding them in fixed positions, but they can still vibrate so have still some kinetic energy.

Question 19

Using the kinetic model, how atoms or molecules arranged in liquids ?

Answer 19

In liquids the atoms or molecules are still very close together but they have more kinetic energy than in solids. They can also change position and flow past each other.

Question 20

Using the kinetic model, how are atoms or molecules arranged in gases

Answer 20

In gases the atoms or molecules have more kinetic energy than those in liquid and they are further apart. They are free to move past each other as there are negligible electrostatic forces between them, unless they collide with each other or the walls of the container. They move randomly with different speeds in different directions

Question 21

Describe what happens when a solid is heated.

Answer 21

When a solid is heated, the particles gain more energy and vibrate more vigorously. Eventually they may break away from the solid structure and become free to move around, meaning it has turned into a liquid.

Question 22

Describe what happens when a liquid is heated.

Answer 22

When a liquid is heated, some of the particles gain enough energy to break away from other particles. The particles which escapes from the body of the liquid become a gas

Question 23

Why is ice less dense than water?

Answer 23

Because the particles in a solid arrangement are held slightly further apart than the particles in their random arrangement in liquid water

Question 24

Define the internal energy

Answer 24

the sum of the randomly distributed electrostatic kinetic and potential energies of atoms or molecules within the substance.

Question 25

A gas has an internal energy of 100J and a mass of 3g. What’s the kinetic energy of its particles?

Answer 25

100J .

this is because the electrostatic forces in a gas are negligible unless when particles are colliding, hence the potential energy will be 0J. From there using the formula relating internal energy, electrostatic kinetic and potential energies, we can deduce that the kinetic energy must be equal to the internal energy.

Question 26

If two objects are said to experienced a gravitational force, they are said to have a gravitational potential energy. If two objects are said to experience an electrostatic attraction/force, then they are said to have…

Answer 26

an electrostatic potential energy

Question 27

When a substance change phase the temperature…

Answer 27

does not change, nor does the kinetic energy of the particles, but the electrostatic potential energy does change significantly

Question 28

In different phases of matter, the electrostatic potential energies have…

Answer 28

different values

Question 29

The electrostatic potential energy in gases is

Answer 29

0

Question 30

The electrostatic potential energy in liquids is

Answer 30

a negative value, where the negative sign means that energy must be supplied to break the atomic or molecular bonds

Question 31

The electrostatic potential energy in solids is

Answer 31

a large negative value, where the negative sign means that energy must be supplied to break the atomic or molecular bonds

Question 32

state the phases of matter in descending order based on their electrostatic potential energy

Answer 32

gases - 0J
liquids - (-ve) J
solids - (-ve) J

Question 33

How can u test for the specific heat capacity of a substance?

Answer 33

By using the specific heat capacity equation and substituting E with E=(It)V, where V and I are got from reading an ammeter and voltmeter of a circuit that supplies a stable current to heat an object via a heater.

Question 34

A substance is cooled until it reaches -273.15*C. Identify all the statements below which accurately describe the energy of the substance.

A Its internal energy is not at its minimum value.
B Its internal energy is at its non-zero minimum value.
C Its internal energy is at its minimum value of zero.
D Its particles’ kinetic energy is zero.
E Its particles’ potential energy is zero.
F The substance is at absolute zero.
G The substance can be cooled further.

Answer 34

B, D, F.

Question 35

Why will a substance at absolute zero still have a non zero internal energy?

Answer 35

Because the electrostatic potential energy is unaffected by the change in temperatures.

Question 36

Can the internal energy of an object decrease further if the object has a temperature of absolute zero?

Answer 36

No because the kinetic energy will be 0 and the electrostatic potential energy will not change unless a change of state/phase occurs, which cannot occur at or below absolute zero, as the absolute zero is the lowest temperature possible in the universe.

Question 37

Can the electrostatic potential energy of an object decrease further if the object has a temperature of absolute zero?

Answer 37

No because the electrostatic potential energy will not change unless a change of state/phase occurs, which cannot occur at or below absolute zero, as the absolute zero is the lowest temperature possible in the universe.

Question 38

The specific heat capacity of water is 4181Jkg^{-1}K^{-1}. What does the word ‘specific’ mean?

Answer 38

per unit mass

Question 39

Define specific latent heat

Answer 39

Specific latent heat capacity is the energy required per unit mass to change the phase of a substance, while at constant temperature.

Question 40

the specific capacity is independent of the…

Answer 40

mass

Question 41

Explain what happens when 2 substances in contact have different temperatures.

Answer 41

If two substances are in contact, and one is hotter than the other, then there will be a net flow of thermal energy from the hotter object to the cooler object. The hotter object will cool down and the cooler one will warm up, until they are at the same temperature, where there will be no net energy transfer. Two objects are in thermal equilibrium when there is no net transfer of thermal energy between them.

Question 42

Describe how this graph leads to the concept of an absolute zero of temperature.

Answer 42

Idea of extrapolating graph back (to negative temperatures)
Volume is zero at absolute zero / negative volumes are impossible

Question 43

Fig. 6.1 shows the apparatus used to observe Brownian motion using pollen grains suspended in a liquid.
State two conclusions that may be deduced about the molecules of the liquid from the motion of the pollen grains observed with the microscope.

Answer 43

Molecules (of the liquid) are in random/haphazard motion (AW)

Molecules (of liquid) are smaller than pollen grains