P2

Question 1

Properties of liquids

Answer 1

Arrangement: Close but not in a regular repeating pattern

Motion: Slide past each other and move to a certain extent

Intermolecular forces: Weaker than solids

Incompressible

Fixed volume

Fixed shape flow

Question 1

Properties of solids

Answer 1

Arrangement: Closely packed

Motion: Vibrate around a fixed position

Intermolecular forces: Strong between moecules

Incompressible

Fixed volume

Fixed shape no flow

Question 2

Properties of gas

Answer 2

Arrangement: Randomly and far apart

Motion: Random and fast motion, colliding often

Intermolecular forces: Practically non existent

Compressible

Unfixed volume

Unfixed shape flowss

Question 3

What is brownian motion

Answer 3

Large Particles suspended in fluids that move randomly

Question 4

Why does brownian motion occur

Answer 4

they’re colliding with the existing fast moving particles in the fluid

Question 5

what can be observed in experiments relating to brownian motion

Answer 5

Random movements of suspended particles in a fluid

Question 6

What does brownian motion prove

Answer 6

The kinetic model of matter as it proves that particles are in constant motion

Question 7

What does brownian motion prove other than the kinetic model of matter

Answer 7

That large particles can be moved by lighter faster moleculus

Question 8

What is diffusion

Answer 8

The movement of particles from an area of high concentration to a low concentration

Question 9

How does molecular mass affect rate of diffusion

Answer 9

The lighter molecular mass the faster rate of diffusion. As they have a higher speed, leading to more collisions, which contribute to a faster rate of diffusion

Question 10

How does temperature affect rate of diffusion

Answer 10

• higher temp = faster diffusion
• higher internal inergy for particles so move at faster speed
• more collisions

Question 11

What 2 marks need to be put on a thermometer to calibrate it put degrees on it before use

Answer 11

The lower fixed point (temp. of ice) which should be 0 degrees

The upper fixed point (temp. of steam) which should be 100 degrees.

Question 12

What properties affect the sensitive of a theometer

Answer 12

A bigger bulb
A liquid with greater expansivity
A thinner capillary tube

Question 13

What does linearity indicate for therometers

Answer 13

The change in temperature producing the same change in length

Question 14

What does sensitivy indicate for therometers

Answer 14

The change in length per change in temperature

Question 15

What does range mean in therometers

Answer 15

difference between the maximum and minimum temperatures that the thermometer can read.

Question 16

What’s the structure of a thermocouple

Answer 16

2 metal wires made from different metals joined at one making the hot junction where what they measure is placed and then connected to one end of the measuring instrument cold junction

Question 17

How does a thermocouple work

Answer 17

It relies on the fact the temp. difference between the interection of metal and measuring instrument creates a voltage which is equal to the temperature of that object

Question 18

Why are thermocouples used

Answer 18

they’re highly responsive and can measure a very high range of temperatures

Question 19

What’s thermal expansion

Answer 19

• particles receive thermal and energy and vibrate vigorously
• cause spacing between particles to increase, expanding the material

Question 20

What is thermal expansion caused by

Answer 20

Heat energy through heat that causes particles to vibrate more vigorously

Question 21

Examples of thermal expansion

Answer 21

Railroad tracks, therometers

Question 22

Order of magnitude of expansion in states of matter

Answer 22

Gas>Liquid>Solid

Question 23

Why is gas most sensitive to thermal expansion

Answer 23

• most freedom of motion
• intermolecular forces extremely weak

Question 24

What changes during changes of state

Answer 24

Arrangement, motion, and closeness

Question 25

What's internal energy

Answer 25

The energy of particle motion and chemical bonds

Question 26

Ranking of internal energy between states

Answer 26

Gas>Liquid>Solid

Question 27

Do temperatures of substance change during changes of state

Answer 27

No despite energy being transferred they're used to break bonds which dissipates the temperature.

Question 28

What do the flat parts of a changing state graph mean

Answer 28

melting, freezing, boiling, condesning, and others

Question 29

What is evaporation

Answer 29

the surface level change of state from liquid to gas

Question 30

What kind of particles are eligible for evaporation

Answer 30

fasting moving ones near the surface of a liquid

Question 31

What does evaporation lead to

Answer 31

the cooling of a liquid as it takes the fastest moving meaning hottest particles away.

Question 32

Differences between boiling and evaporation

Answer 32

boiling only occurs after a specific temperature is reached, evaporation occurs no matter the temperature boiling is occuring throughout the liquid, evaporation only happens at the surface

Question 33

Factors that affect rate of evaporation

Answer 33

Airflow increase evaporation increase Suface area increase rate of evaporation increase Temperature increase rate of evaporation increases

Question 34

What is pressure exactly

Answer 34

Force per unit area caused by molecules hitting the sides of the containor

Question 35

Is pressure equal throughout a containor

Answer 35

yes as there's a equal amount of molecules hitting all sides of the containor

Question 36

What do particles do when they rebound against sides of containors

Answer 36

they exert a force which keeps the shape against atmospheric pressure

Question 36

What factors affect pressure

Answer 36

temperature within containor as particles with higher speed will have more frequencies of colliosions against a containor size of containor or volume lesser volume leads to a higher pressures as there's less distance needed to be travelled to collide against the sides of the containor

Question 37

What relationship does pressure and volume have

Answer 37

a inverse relationship pressure increases as volume decreases

Question 38

What is conduction

Answer 38

the transfer of thermal energy by particles bumping against each other

Question 39

Why are metals the best at conduction compared to gases or liquids

Answer 39

as their arrangement is closely packed and they have delocalised electrons that help pass along the energy

Question 40

What are examples of good conductors

Answer 40

metals (copper, aluminium, e.t.c)

Question 41

What are examples of insulators

Answer 41

non-metals (wood and plastic)

Question 42

What is convection

Answer 42

the main method of energy transfer by fluids, as it requires flow of particles

Question 43

What is the convection current

Answer 43

- particles heated, move faster, take up more space, decreasing density, float up - cools, thus sinking down - pushed by particle behind to recieve heat again

Question 44

What's raidation

Answer 44

the transfer of heat by waves most commonly infrare waves

Question 45

Why can we feel the heat from the sun

Answer 45

radiation and radiation only bc. its only the method of heat transfer that doesn't require a medium

Question 46

Properties of surfaces on radiation

Answer 46

Black surfaces; Absorb and emit radiation the best They will gain and lose heat the fastest White surfaces: reflect radation the most It will not be easy for it to gain heat Matte or dull surfaces: Increase absorption and decrease reflection Easy to gain heat Shiny surfaces: Increase reflection and decrease absorption. Hard to gain heat