1 States of matter

Question 1

What are the three states of matter?

Answer 1

• Solid
• Liquid
• Gas

Question 2

What is the arrangement of particles in solids?

Answer 2

• Arranged regularly and packed closely
• Only able to vibrate in fixed positions
• Strong forces of attraction which keep them together

Question 3

What is the arrangement of particles in liquids?

Answer 3

• Mostly touching but there are some gaps
• Less dense than solids
• Not a very strong force of attraction as they can move around eachother.

Question 4

What is the arrangement of particles in gases?

Answer 4

• Moving randomly at a high speed in all directions
• Particles are much further apart
• Almost no forces of attraction between the particles

Question 5

Most to least kinetic energy?

Answer 5

Gases –> Liquids –> Solids

Question 6

How does melting happen?

Answer 6

The energy provided by the heat source makes the particles in the solid vibrate faster and faster. They then vibrate so fast so they break the bonds between them because the particles are not strong enough to hold each other together.

Question 7

What has to be supplied to convert a solid to a liquid?

Answer 7

Energy, as liquids have more kinetic energy than solids.

Question 8

What is melting?

Answer 8

When a solid changes to a liquid.

Question 9

What is the melting point?

Answer 9

The temperature at which the solid melts.

Question 10

What happens to the energy in melting?

Answer 10

We put energy in as liquids have more kinetic energy.

Question 11

How does freezing happen?

Answer 11

The liquid particles will slow down and eventually they will be moving so slowly that the forces of attraction between them will hold them in a fixed position and the particles pack more closely together to form a solid.

Question 12

What is freezing?

Answer 12

When a liquid changes to a solid.

Question 13

What is the freezing point?

Answer 13

The temperature at which a liquid freezes.

Question 14

What is boiling?

Answer 14

When a liquid turns into a gas.

Question 15

How does boiling happen?

Answer 15

When a liquid is heated so strongly that the particles are moving fast enough to overcome all of the forces of attraction between them.
Vibrate fast enough to completely break free of the bonds.

Question 16

What happens when there are stronger forces of attraction between particles?

Answer 16

More heat is needed so it has a higher boiling point, as more energy is needed to overcome these forces of attraction.

Question 17

What is condensing?

Answer 17

When a gas turns into a liquid.

Question 18

How does condensing happen?

Answer 18

When a gas is cooled, the particles move slowly enough that forces of attraction between them start to form and hold them together as a liquid

Question 19

What is evaporation?

Answer 19

The change of state from a liquid to a vapour. It occurs at a temperature below the boiling point and only at the surface of the liquid.

Question 20

What happens during evaporation?

Answer 20

Some very fast particles at the surface of the liquid will have enough energy to overcome the forces of attraction between the particles, so they will break away to form a gas.

Question 21

How does evaporation happen in a closed container?

Answer 21

The particles in the gas will also be colliding with particles at the surface of the liquid.

Question 22

How does evaporation happen in an open container?

Answer 22

The liquid just slowly disappears to the air.

Question 23

What is sublimation?

Answer 23

The conversion of a solid into a gas.

Question 24

What is deposition?

Answer 24

The conversion of a gas into a solid.

Question 25

What state of matter is a substance at when it is below its melting point?

Answer 25

Solid.

Question 26

What state of matter is a substance at when it is between its melting and boiling point?

Answer 26

Liquid.

Question 27

What state of matter is a substance at when it is above its boiling point?

Answer 27

Gas.

Question 28

What makes a higher melting and boiling point?

Answer 28

The stronger the forces of attraction between particles.

Question 29

What is diffusion?

Answer 29

The random movement of particles from an area of high concentration to an area of low concentration.

Question 30

How do you show diffusion in gases?

Answer 30

The lower gas jar contains bromine gas; the top one contains air. If the lids are removed, the brown colour of the bromine diffuses upwards until both gas jars are brown.

Question 31

In this apparatus do the air particles also move downwards?

Answer 31

Yes.

Question 32

What do the bromine particles and air particles create when they move around at random?

Answer 32

An even mixture - as both gas jars contain air and bromine particles.

Question 33

What are the precautions taken in the experiment to do with diffusion of gases?

Answer 33

This experiment must take place in a fume cupboard as inhalation of bromine could cause a reaction.

Question 34

What is the other way of showing diffusion in gases?

Answer 34

With hydrogen and oxygen. You have to put at lighted splint in at the end to find out where each gases have gone.

Question 35

What is the conclusion gained from the hydrogen and oxygen experiment.

Answer 35

That there is an equal mixture of hydrogen and oxygen in both jars, so you will get identical explosions.

Question 36

Which is the experiment that shows how particles of different gases travel at different speeds?

Answer 36

It is the experiment which relies on the reaction between ammonia and hydrogen chloride which produces white sodium ammonium chloride.

Question 37

What is the method of this experiment to show that gases travel at different speeds?

Answer 37

Pieces of cotton wool are soaked in concentrated ammonia solution (for ammonia gas) and concentrated hydrochloric acid (for hydrogen chloride gas), and are placed in the end of a long glass tube with rubber bungs on each end.

Question 38

What are the precautions taken by this experiment to show that gases travel at different speeds?

Answer 38

• Rubber bungs stop the poisonous gas from escaping.

Question 39

What are the results gained from the experiment to show that gases travel at different speeds?

Answer 39

Ammonia and hydrogen particles diffuse along the tube, and a white ring forms where they meet and it takes some time to form, and appears closer to the hydrochloric acid end

Question 40

Why does it take time for the white ring to form?

Answer 40

As it takes some time for the particles of ammonia and hydrogen chloride to diffuse along the tube.

Question 41

Why does the white ring form closer to the hydrochloric acid end?

Answer 41

Ammonia particles are lighter than the hydrochloric acid particles so they move faster. The ammonia particles travel further away in the same amount of time, which means that the ring forms further away from the ammonia end.

Question 42

How do you show the diffusion in liquids?

Answer 42

With potassium manganate and water.

Question 43

What is the method used in the experiment to show the diffusion of liquids?

Answer 43

A small jar of potassium manganate solution is placed in a gas jar of water, it can take days for the colour to diffuse throughout all the water.

Question 44

Why could it take days for the colour to diffuse throughout all of the water?

Answer 44

This is because particles in a liquid move more slowly than the particles in a gas. The particles in a liquid are also much closer together than those in a gas and so there is less space for particles to move into without colliding with another one.

Question 45

What is the solvent?

Answer 45

The liquid that a solute dissolves in.

Question 46

What is the solute?

Answer 46

The substance that dissolves in a solvent.

Question 47

What is the solution?

Answer 47

The mixture formed when a solute dissolves in a solvent.

Question 48

What is a saturated solution?

Answer 48

A solution that contains as much dissolved solid as possible at a particular temperature.