States of Matter Flashcards

(77 cards)

1
Q

What does the particle model do?`

A

Explains state changes in a substance in terms of the arrangement, movement and energy stored in its particles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the arrangement of particles in a gas, liquid and solid

A

Gas - random and far apart
Liquid - random and close together
Solid - regular and close together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the movement of particles of the 3 states of matter

A

Gas - fast in all directions
Liquid - move around each other
Solid - vibrate about fixed positions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

State changes are physical changes. What does this mean?

A

They can be reversed and the chemical properties of the substance don’t change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What do state changes change?

A

The particles’ arrangement, their movement and the amount of stored energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is sublimation?

A

From solid to gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is deposition?

A

From gas to solid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

With what information can you predict the state of a substance?

A

If you know its melting point, boiling point and temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

If a substance is below its melting point, what state is it in?

A

The solid state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

If a substance is between the melting and boiling point, what state is it in?

A

The liquid state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

If a substance is above the boiling point, what state is it in?

A

The gas state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Can the composition of a pure substance be changed?

A

No and it is the same in all parts of a piece of the substance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a mixture?

A

A substance that contains elements and/or compounds that are not chemically joined together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why can’t we separate pure substances using physical methods like filtering or picking bits out?

A

Because it has the same fixed composition in all its parts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Why can you use physical methods to separate a mixture?

A

Because it does not have a fixed composition

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens when a solid melts?

A

Its particles gain enough energy to overcome the weak forces of attraction between them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Give an example of a phyiscal poroperty

A

Melting point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a solution?

A

A mixture made up of solutes in a liquid called the solvent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is a solute?

A

Dissolved substance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is crystallisation?

A

When solutes are separated by evaporating the solvent to leave the solutes behind

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is a saturated solution?

A

A solution that contains the maximum amount of solute that can dissolve in that amount of solvent at that temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the filtrate?

A

The solvent and solute (s) that pass through the fine holes in the filter paper

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the residue?

A

The bits of insoluble substances that can’t fit through the filter paper holes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is a risk assessment?

A

Where the hazards of doing an experiment are identified

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is the use of chromatography?
To find out which coloured compounds a mixture contains
26
What is the solvent in paper chromatography called?
The mobile phase
27
What phase the paper in paper chromatography contain?
The stationary phase, through which the solvent and dissolved substances move
28
What is the name of the paper with the separated components on it called?
A chromatogram
29
What is the Rf value in paper chromatography?
The distance the compound has rises divided by the distance the solvent has risen
30
How do you calculate the Rf value?
Rf = Distance moved by the spot/Distance moved by the solvent
31
What can paper chromatography be used for?
-Distinguish between pure and impure substances -Identify substances by comparing the pattern on the chromatogram with the patterns formed by known substances Identify substances by calculating their Rf value
32
What is distillation?
The process of separating the components or substances from a liquid mixture by using selective boiling and condensation
33
What is the name of the apparatus used in distillation?
A still
34
What is fractional distillation?
A distillation process that separates 2 or more liquids
35
How can fractional distillation work>
Some liquids boil more easily than others due to their different boiling points, and so one will turn into vapour first
36
What is desalination?
Producing pure water from sea water
37
How does desalination work?
Using simple distillation - sea water is heated so that water vapour leaves it quickly. This vapour is then cooled and condensed, forming water without the dissolved salts
38
Why is simple distillation usually not a suitable method for producing large volumes of drinking water?
A lot of energy must be transferred to sea water for this to happen
39
What doe chemical analysis involve?
Using chemical reactions or sensitive machines to identify and measure the substances in a sample
40
What are aquifers?
Underground rocks containing groundwater
41
What are the 3 steps of water treatment?
Filtration, sedimentation and chlorination
42
Why is chlorination an important part of water treatment?
Because the chlorine kills the microorganisms in the treated water
43
What kind of melting points do pure substances have?`
Sharp melting points
44
What do mixtures melt over?
A range of temperatures - no sharp melting points
45
What is a pure substance?
Substance that contains only 1 element/compound
46
What happens when salt is added to water?
It lowers the freezing point and it weakens the rigid lattice structure and molecules are disordered
47
What does insolubke mean?
Doesn't dissolve
48
How do you purify a liquid?
By removing solid impurities from it
49
Why does filtration work?
They have tiny pores that are: - large enough to let water molecules/dissolved substances through - small enough to stop insoluble solid particles getting through
50
What do you use crystallisation for?
To produce solution crystals from a solution
51
What is a saturated solution?
A solution that can't hold any more solute
52
Why is a hot water bath preferred for crystallisation?
Gives you more control over heating than a Bunsen Burner flame directly on the evaporating dish
53
What is solubility?
The mass of a solute that dissolves in a given volume of a solvent at a given temperature
54
Why does crystallisation work?
- The solubility of the solute decreases as the saturated solution cools - Crystals form from the excess solute
55
What happens when salt is added to water?
It lowers the freezing point and it weakens the rigid lattice structure and molecules are disordered
56
What does insolubke mean?
Doesn't dissolve
57
How do you purify a liquid?
By removing solid impurities from it
58
Why do you use a lid in paper chromatography?
It stops evaporation of the solvent
59
What do you use crystallisation for?
To produce solution crystals from a solution
60
What is a saturated solution?
A solution that can't hold any more solute
61
Why is a hot water bath preferred for crystallisation?
Gives you more control over heating than a Bunsen Burner flame directly on the evaporating dish
62
What is solubility?
The mass of a solute that dissolves in a given volume of a solvent at a given temperature
63
Why does crystallisation work?
- The solubility of the solute decreases as the saturated solution cools - Crystals form from the excess solute
64
What is the stationary phase?
A substance that does not move (the chromatography paper)
65
What is the mobile phase?
A substance that moves through the stationary phase (the solvent)
66
What happens during chromatography?
Each soluble substance in the mixture forms bonds with the two phases, but if it moves or not depends on which bonds are stronger: - Stationary phase - stay near bottom of paper - Mobile phase - move towards the top
67
Why do you use a lid in paper chromatography?
It stops evaporation of the solvent
68
What can you use a chromatogram for?
- Distinguish between pure and impure substances - Identify a substance by company of pattern of spots with those of a known substance - Identify substances using Rf values
69
Are soluble compounds carried up the paper faster or slower?
Faster than less soluble ones, so the compounds separate out
70
How do you make pure water?
Using distillation - separating it from dissolved solids
71
Why does distillation work?
When the mineral water evaporates, only the water turns to gas (vapour) and so it leaves the solid minerals with much higher boiling points behind. The pure vapour is then condensed, making a pure liquid
72
In distillation, what is a condenser?
A central tube surrounded by a jacket of cold water. It keeps the tube cool, so that almost all of the vapour condenses and turns into a liquid
73
What do anti-bumping granules do?
Make the liquid boil more smoothly; small bubbles of vapour form on the corners of the granules and reduce the risk of the liquid boiling over
74
What is fractional distillation and why does it work?
The separation of a mixture into its component parts; some liquids boil more easily than others and will turn into vapour first
75
What are the 3 stages of water treatment in order?
Sedimentation - large insoluble particles (like stone) sink to the bottom of the tank Filtration - small insoluble particles are removed by filtering through beds of sand (water can get through sand but small insoluble particles stay at the top) Chlorination - chlorine gas is bubbled from the water to kill microbes
76
Give an advantage and disadvantage of simple distillation of sea water
Advantage - kills microbes in the sea water/produces pure water/uses plentiful raw materials Disadvantage - needs a lot of energy to heat the water
77
Why does the temperature remain constant during melting?
It is an isothermal process, meaning the temperature remains constant. The energy goes directly into changing the phase and state of the substance as opposed to changing the temperature of the substance