Solids, Liquids And Gases

Question 1

Equation for density

Answer 1

Mass (kg)
—————
Volume (m cubed)

Question 2

What is density?

Answer 2

A measure of how much mass a substance has, per unit of its volume

Question 3

1g/cm cubed = …?

Answer 3

1,000kg/m cubed

Question 4

How do you measure the mass of a solid?

Answer 4

Put it on a mass balance

Question 5

How do you measure the volume of a solid with a regular shape?

Answer 5

Measure and multiply its length, width and height

Question 6

What is an outlet on a eureka can?

Answer 6

It allows the water to flow out and be collected by the measuring cylinder

Question 7

How do you measure the volume of a solid with an irregular shape?

Answer 7

Use a eureka can that’s been filled right up to the outlet with water and an empty measuring cylinder
When you add the solid substance to the eureka can, a volume of water, exactly equal to that solid, will flow out of the can and into the measuring cylinder
—> allowing us to measure the exact volume of the solid

Question 8

How do you find the density of a solid?

Answer 8

Put the mass and the volume values into the equation (m/v)

Question 9

How do you find the density of a liquid?

Answer 9

Place an empty measuring cylinder onto a balance and zero the balance to re-set it
Pour some of the liquid into the cylinder (e.g. 10ml = 10cm cubed)
Record the mass of that amount of liquid
—> take multiple measurements so that you can identify any anomalies and calculate a mean
Divide the mass by the volume to give us the density

Question 10

The larger the volume that you measure, the …? (Finding the density of a liquid)

Answer 10

The more accurate your density will be

Question 11

Why does using a larger volume to find the density of a liquid make the density value more accurate?

Answer 11

It minimises the effects of the uncertainty in taking your measurements

Question 12

What is pressure?

Answer 12

The force per unit of area

Question 13

Equation for pressure

Answer 13

Force (N)
——————
Area (m squared)

Question 14

What is pressure measured in?

Answer 14

Pascals

Question 15

How is pressure created in a solid?

Answer 15

The collision of 2 solid objects

Question 16

How is pressure created in fluids?

Answer 16

The particles that they’re made of constantly collide into their surroundings and generate pressure

Question 17

Gas in a container (pressure)

Answer 17

The collisions of the gas particles with the wall would create pressure
—> because each collision applies a force to the inside area of the container

Question 18

Liquid in a beaker (pressure)

Answer 18

It would apply forces outwards in all directions
—> because the water particles will collide with the glass walls on the sides and bottom and with the air at the surface
—> creates pressure

Question 19

What force do we use for pressure?

Answer 19

The perpendicular force

Question 20

What is the perpendicular force?

Answer 20

The component of the force which is at right angles to the surface it’s colliding with

Question 21

If a particles collides with the wall at an angle, then …?

Answer 21

Less force is exerted onto the wall it’s colliding with
—> means a lower pressure

Question 22

If particles collide with the wall at a perfect right angle (perpendicularly), then …?

Answer 22

The entire force is exerted onto the wall it’s colliding with
—> higher pressure

Question 23

What is most of the pressure acting on an object in water due to?

Answer 23

The surrounding water molecules that are constantly colliding with is

Question 24

What is the small component of pressure due to (when an object is placed in water)?

Answer 24

The weight of all the water above the object

Question 25

When is the weight of the water above the object felt as?

Answer 25

A downwards force

Question 26

As the object moves deeper into the water, the …?

Answer 26

Amount of pressure due to its weight will increase —> because there will be more and more water above the object

Question 27

What also determines the pressure?

Answer 27

The density of the liquid

Question 28

The denser the liquid, the …?

Answer 28

Larger its mass per unit of volume —> the larger its weight will be

Question 29

What is another factor of pressure?

Answer 29

Gravitational field strength

Question 30

What does the gravitational field strength determine?

Answer 30

The weight for a given mass

Question 31

A bigger gravitational field strength would mean a …?

Answer 31

Larger weight

Question 32

Equation for pressure in a liquid

Answer 32

P = hpg

Question 33

What does the ‘h’ in the equation for pressure in a liquid stand for?

Answer 33

The height of the column of the liquid (The depth, m)

Question 34

What does the ‘p’ in the equation for pressure of a liquid stand for?

Answer 34

The density (kg/m cubed)

Question 35

What does the ‘g’ in the equation for pressure in a liquid stand for?

Answer 35

Gravitational field strength (N/kg)

Question 36

What is upthrust due to?

Answer 36

The collisions of all the tiny water molecules around the box

Question 37

What will the surrounding water (to the box in water) exert?

Answer 37

Forces on the box from all directions

Question 38

Why does the bottom of the box experience a larger upwards force than it will a downwards force from the top?

Answer 38

Because it is deeper than the top —> means that overall, there will be a resultant force upwards which pushes the box up (upthrust) and it will float

Question 39

What do we have to consider (about upthrust)?

Answer 39

The object’s weight —> that acts downwards and so pulls the object down

Question 40

If the upthrust is larger than the weight, then it will …?

Answer 40

Float

Question 41

If the weight is larger than the upthrust, then it will …?

Answer 41

Sink

Question 42

What will happen to the object if it is more dense than the liquid’s density?

Answer 42

It will sink

Question 43

What will happen if the density of an object is less dense than the liquid’s density?

Answer 43

Then it will float

Question 44

What is the atmosphere?

Answer 44

A thin layer of gases that surrounds our entire planet

Question 45

What gases make up the atmosphere?

Answer 45

Nitrogen Oxygen Greenhouse gases Ozone layer

Question 46

What do the greenhouse gases do?

Answer 46

Keep the planet warm

Question 47

What does the ozone layer do?

Answer 47

Keeps out the most harmful radiation

Question 48

Where is the density of particles highest?

Answer 48

Near the earth’s surface (sea level)

Question 49

What gets smaller the further away you are from the Earth?

Answer 49

The pressure

Question 50

Where are there more collisions with the surface of an object?

Answer 50

At sea level

Question 51

Where are there less collisions with the surface of an object?

Answer 51

Really high up

Question 52

What does more collisions mean?

Answer 52

There will be a greater force

Question 53

Greater force means …?

Answer 53

Higher pressure

Question 54

What do objects at sea level have?

Answer 54

A huge weight pressing downwards

Question 55

Why do objects at sea level have a huge weight pressing downwards?

Answer 55

Because of the weight of all those particles above it —> as weight is a force, it will contribute to its pressure

Question 56

What will objects at 1000m up in the air have a lot fewer of?

Answer 56

Particles above it

Question 57

What will be smaller when an object is 1000m up in the air and has a lot fewer particles above it?

Answer 57

The force of weight

Question 58

What happens whenever gas particles collide with the walls of a container?

Answer 58

They exert a force —> creates pressure

Question 59

What 2 things does total pressure depend on?

Answer 59

1) how many of these collisions there are 2) how much energy each collision involves

Question 60

What 3 factors affect pressure?

Answer 60

Temperature Concentration Volume

Question 61

What happens when you heat up a gas?

Answer 61

We would be transferring energy to the particles kinetic energy store and so they will start to move around faster

Question 62

What will happen when the particles gain kinetic energy and start to move around faster?

Answer 62

There will be more collisions with the walls of the container —> each individual collision would involve more force

Question 63

What does pressure increase with?

Answer 63

Temperature

Question 64

What happens if we increase the number of particles in our container, but keep the volume the same?

Answer 64

We will have increased the concentration

Question 65

What does an increased concentration mean?

Answer 65

There will be more particles to collide with the walls —> more collisions means a higher pressure

Question 66

What does more collisions mean?

Answer 66

A higher pressure

Question 67

As concentration increases, …?

Answer 67

Pressure increases

Question 68

What would happen if we made the container smaller, but kept the number of particles the same?

Answer 68

Then there would be more particles per unit of volume —> the same as a higher concentration of particles

Question 69

If the volume of the container decreased what will the particles do?

Answer 69

Because the particles no longer have as far to travel between each collision, there will now be more collisions —> means a higher pressure

Question 70

As volume decreases …?

Answer 70

Pressure increases

Question 71

What does it mean if the container the particles are in is a balloon?

Answer 71

Then it is flexible and so you can expand or shrink it

Question 72

What do changes to temperature and concentration do to the balloon?

Answer 72

Change the volume of the container rather than the pressure

Question 73

What 2 factors affect the volume of a flexible container?

Answer 73

Temperature Concentration

Question 74

Why does the volume increase instead of pressure in a flexible container when the temperature or concentration increases?

Answer 74

Any increase in a number or the force of the collisions will just cause the balloon to expand rather than increasing its pressure

Question 75

What would happen in reality to a flexible container if the temperature or concentration increases?

Answer 75

Volume and pressure will increase because the balloon can only expand so much

Question 76

How are pressure and volume related?

Answer 76

Inversely related/proportional

Question 77

What does inversely related/proportional mean?

Answer 77

As one goes up, the other goes down

Question 78

What does pressure and volume being inversely related/proportional mean?

Answer 78

That for a given amount of gas, at a constant temperature, the pressure x the volume will always be a constant value

Question 79

Pressure x volume = …?

Answer 79

Constant

Question 80

What would happen to the pressure if the volume increased?

Answer 80

The pressure would decrease —> when multiplied together they’d still give the same value