Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Chemistry > Chapter One > Flashcards

Chapter One Flashcards

Materials in our world

You may prefer our related Brainscape-certified flashcards:
Periodic Table flashcards Chemistry 101 flashcards AP® Chemistry flashcards Organic Chemistry 101 flashcards
1
Q

What are Materials?

A
  • Substances used to make objects
  • Can be a mixture of substances or pure elements/compounds
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Examples of materials

A
  • Wood
  • Nylon
  • Paper
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Substances not considered materials

A

Chemicals such as hydrochloric acid, chlorophyl and carbon dioxide

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

Definition: Element

A

Pure substances that are made up of just one type of atom

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

Example of an element

A
  • Carbon
  • Gold
  • Silver
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are Compounds?

A
  • Pure substances made up of more than one type of atom
  • They consist of more than one type of element in fixed proportions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Examples of compounds

A
  • SiO2 (silica)
  • H2O (water)
  • C6 H12 O6 (glucose)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Chemical/physical properties that influence a materials use

A
  • Colour
  • Hardness
  • Melting point
  • Boiling point
  • Conduction of electricity
  • Conduction of heat
  • Ability to react with other chemicals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Can properties of elements/compounds be altered

A

Thay cannot be as they are pure substances

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

How are the properties of elements/compounds determined

A

Determined by the arrangement of their atoms molecules and are distinct and measurable for given arrangement of atoms and molecules

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

Can properties of mixtures change

A

Can be changed depending on the concentration of each element in the mixture which makes them very useful materials

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

What is Mixture?

A

A physical combination of two or more substances that do not change their chemical makeup or form or break bonds with each other

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

What are Metals properties?

A
  • High tensile strength
  • Ductility
  • Malleability
  • Shiny luster
  • High melting point
  • Thermal conductivity
  • Electrical conductivity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Categories of materials

A
  • Metals
  • Polymers
  • Ceramics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is Metals?

A
  • Valuable materials due to their properties
  • 80% of all known elements
  • Found in elemental metallic forms and as compounds known as minerals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How can you improve a metals weak point

A

Use an alloy of the metal

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

What are Alloy?

A

A mixture of a metal with other metals or small amounts of non-metals

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

What are Polymers?

A
  • A material with a molecular structure that is composed of many repeating smaller units bonded together
  • Includes plastics, nylon and rubbers
  • Natural and synthetic polymers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Properties of Polymers

A
  • Less dense
  • Corrosion resistant
  • Electrical resistance
  • Polymers of biological nature offer good compatibility with human skin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are Ceramics?

A
  • An inorganic, non-metallic solid
  • Natural and synthetic ceramics
  • The degree of order within ceramic materials can range from highly ordered to highly irregular
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Example of natural polymers

A
  • Wool
  • Paper
  • Silk
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Example of synthetic polymers

A

Polystyrene

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

Example of natural ceramics

A

Kaolinite (used to make porcelain)

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

Example of synthetic ceramics

A

Silicon carbide (used as an abrasive)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is a structure that is highly ordered called?

A

Crystalline

26
Q

Highly irregular

A

Amorphous

27
Q

What are Composite materials?

A
  • A combination of two or more distinct materials with distinctly different physical or chemical properties
  • Has properties that are unobtainable by using an individual material
28
Q

What are Nanotechnology?

A

The science that investigates the design, properties and application of materials on the nanoscale

29
Q

What is a Nanoscale?

A
  • Structures between 1 and 100 nanometers across
  • 1 nanometre is a billionth of a metre
30
Q

What are Nanomaterials?

A

Substances both natural and synthetic that are composed of single units that exist on the nanoscale

31
Q

Example of nanomaterials

A

Fullerenes (family of carbon molecules)

32
Q

Fullerenes

A

Three-dimensional structures formed by a network of carbon atoms

33
Q

Which fullerene promises the most opportunities

A

The cylindrical tube known as the carbon nanotube

34
Q

Carbon nanotubes

A

Formed from a layer of two-dimensional carbon atoms arranged in hexagons known as graphene

35
Q

Carbon nanotubes properties

A
  • Finds a use as a reinforcement in composite materials
  • Interesting electrical properties
  • Exceptional strength
  • Stiff
  • The base of all superconductor research
36
Q

The two ways materials on the nanoscale can be fabricated

A
  • Bottom-up fabrication
  • Top-down fabrication
37
Q

Top-down fabrication

A

Starts with a material of a much larger scale than desired which is then selectively removed or the size of the material is gradually reduced through grinding until the required shape and size is formed

38
Q

Examples of top-down fabrication

A
  • Computer chips
  • Sunscreen
39
Q

Advantages of top-down fabrication

A

Large quantities of material can be produced cheaply and the product demonstrates good levels of uniformity

40
Q

Disadvantages of top-down fabrication

A

Limited to relatively simple structures and by the scale of the tools used to remove the material from the starting medium

41
Q

Bottom-up fabrication

A

Physically growing or building the required material atom by atom or molecule by molecule until the required shape and size is formed

42
Q

Advantages of bottom-up fabrication

A

Can be used for far more complicated structures due to the ability of being able to manipulate atoms/molecules at the nanoscale

43
Q

Disadvantages of bottom-up fabrication

A

They do not scale up to commercial levels efficiently and thus are currently only economical for research and niche applications

44
Q

Nanoparticles

A
  • A specific type of nanomaterial
  • Usually spherical with diameters of 1-100nm
  • In this size the properties of materials begin to change from those normally observed for bulk material due to greater contribution of Quantum effects
  • Potential in medicine, physics, optics and electronics
45
Q

Separation techniques using either physical or chemical properties

A
  • Particle size
  • pH
  • Density
  • Solubility
  • Electric charge
46
Q

Separation through particle size

A
  • Sieving
  • Filtration (vacuum and gravitational)
47
Q

Sieving

A
  • Passing a mixture through a mesh, particles smaller than the holes in the mesh will pash through leaving larger ones behind
  • Separate a mixture of solids with different particle size
48
Q

Filtration

A
  • Separate solid particles from liquid or gas
  • Filter paper seperates liquid from solids
49
Q

Gravitational filtration

A
  • Using the weight of the mixture to push the mixture through the filter paper
  • Purified liquid = filtrate
  • Solid = residue
50
Q

Vacuum filtration

A
  • Faster than gravitational and helps dry the residue faster
  • Rubber seal and side arm on the conical flask
51
Q

Separation by density

A
  • Sedimentation and decantation
  • Separation funnels
  • Centrifugation
52
Q

Sedimentation and decantation

A
  • Sedimentation = settling (form of gravitational separation)
  • The liquid can then be separated from the sediment very carefully, pouring the liquid into another container (decantation)
  • Cheap method, large volumes
53
Q

Seperation funnels

A
  • If two different liquids have different densities and are immiscible they can be separated by a separation funnel
  • Liquid- liquid extraction
54
Q

Centrifugation

A

Spinning a mixture rapidly- speeds up the sedimentation process and extracts finer particles that may not settle naturally

55
Q

Seperation by boling point

A
  • Evaporation
  • Distillation
  • Fractional distillation
56
Q

Evaporation

A

The liquid solvent is boiled off to reveal the solid solute

57
Q

Distillation

A

Similar to evaporation but uses an apparatus to recover the evaporated liquid

58
Q

Fractional distillation

A
  • Separate miscible liquids when their boiling points are slightly different
  • Same as distillation flask but with an extra column which allows for increased contact between rising vapour and falling condensate
59
Q

Seperation by electric charge

A

Chromatography

60
Q

Chromatography

A

Separates liquids based on their differing affinity for various materials present in the chromatography apparatus

Chemistry (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions