Brainscape's Knowledge GenomeTM

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


See full index

Chemistry > Structure and Bonding > Flashcards

Structure and Bonding Flashcards

1
Q

What are ions?

A

Charged particles than can be single atoms (Cl^-) or groups of atoms (NO3^-)

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

Which groups of elements readily/easily form ions?

A

Groups 1,2,6 and 7

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

How do groups 1 and 2 form ions?

A

Metals, lose electrons to form positive ions (cations)

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

How do groups 6 and 7 form ions?

A

Non-metals, gain electrons to form negative ions (anions)

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

What does it mean if elements are all in the same group?

A

They have the same number of outer electrons, form ions with the same charges

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

What is ionic bonding?

A

When a metal and a non metal react together.
- metal loses electrons (+ve)
- non-metal gains these electrons (-ve)
- strong electrostatic forces
- oppositely charged ions

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

What is an ionic compound?

A
  • Structure of a giant ionic lattice
  • made up of ions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a giant ionic lattice?

A
  • closely packed lattice arrangement- structure
  • strong electrostatic forces between oppositely charged ions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are properties of ionic compounds?

A
  • High melting and boiling points (strong electrostatic bonds), needs lots of energy to overcome
  • Solid= fixed position, can’t conduct electricity
    Melted= free to move, carry electrical charge
  • Some dissolve in water-> ions free to move, carry electrical charge
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are covalent bonds?

A

When non-metal atoms bond together, sharing a pair of electrons
- electrostatic forces, strong
- in non-metal elements and compounds

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

What are simple molecular substances made up of?

A

Made up of molecules containing a few atoms joined by covalent bonds

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

What are some examples of simple molecular substances?

A
  • Hydrogen
  • Chlorine
  • Oxygen
  • Nitrogen
  • Methane
  • Water
  • Hydrochloric acid (Hydrogen Chloride)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are properties of simple molecular substances?

A
  • Simple molecular structures
  • Strong covalent bond, weak intermolecular forces
  • Low Melting and Boiling point (to melt you only need to break the weak intermolecular forces)
  • Most are gas or liquid at room temp
  • as molecules get bigger, strength of intermolecular forces increases, more energy needed -> Melting and Boiling point increases
  • No charge, don’t usually conduct electricity
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are Polymers?

A
  • lots of small units linked by strong covalent bonds to form a long molecule
  • More energy needed to break them -> intermolecular forces are larger in simple covalent molecules
  • lower boiling points than ionic or giant molecular structures (weak intermolecular forces)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are Giant covalent structure features+ examples?

A
  • High melting and boiling points (strong covalent bonds)
  • Don’t conduct as solid or molten (apart from exceptions like graphite etc)
  • Diamond, Graphite, Silicon dioxide (silica)
  • Macromolecules
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the features of Diamond?

A
  • Each carbon forms 4 covalent bonds, Very rigid structure
  • High melting point, strong covalent bonds
  • Doesn’t conduct electricity
  • Carbon allotrope
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is Graphite ?

A
  • forms 3 covalent bonds, creates layers of hexagons
  • No bonds between layers, free to more over each other-> soft slippery
  • ideal as a lubricant
  • high melting point (covalent bonds in the layers)
  • 1 delocalised electron per atom, conducts electricity and thermal energy
18
Q

What are the features of the structure of Silicon Dioxide (silica)?

A
  • Silicon and Oxygen
  • What sand is made of
19
Q

What is an allotrope?

A

Different structural forms of the same physical element in the same physical state

20
Q

What is graphene?

A
  • a single layer of graphite
  • sheet of carbon atoms joined in hexagons
  • 1 atom thick
  • strong (covalent bonds, light -> can be added to materials to improve strength without adding much weight
  • delocalised electrons, conduct electricity-> can be used in electronics
21
Q

What are Fullerenes?

A

Molecules of carbon, shaped like hollow balls or small tubes

  • Can be arranged as hexagons, pentagons or heptagons (rings of carbon atoms)
  • Cage other molecules-> deliver drugs into the body
  • Huge SA-> industrial catalysts, lubricants
22
Q

What is the Buckminsterfullerene?

A
  • First fullerene to be discovered
  • C60
  • Forms hollow sphere
23
Q

What are nanotubes?

A

Tiny carbon cylinders, formed from fullerenes

  • can conduct electricity and thermal energy
  • high tensile strength (don’t break when stretched)
  • nanotechnology-> used in electronics, strengthen materials without adding weight (tennis racket frames)
24
Q

What is metallic bonding?

A

Strong electrostatic attraction between positive metal ions and delocalised electrons

  • strong
  • metallic elements, alloys
  • delocalised electrons produce properties of metal
  • high melting point (strong electrostatic forces)
  • Solid at room temp
  • good conductors of electricity and heat (delocalised electrons)
  • Malleable (bent, hammered, rolled into sheets) ,layers of metal can slide over each other
25
Q

What is the difference between Alloys and pure metals?

A

Pure metals-> too soft, mixed with other metals to make them harder

Alloys-> harder, more useful

  • Different metals have different sized atoms, distorting layers making it harder for them to slide over, making the material harder
26
Q

What is an Alloy?

A

a mixture of 2 or more metals or a metal and another element

27
Q

What determines what state a substance will be at a certain temperature?

A

The strength of the forces of attraction

28
Q

What does the strength of the forces of attraction depend on?

A

-Material (structure + bonds)
-Temperature
-Pressure

29
Q

How do particles behave in a solid?

A
  • strong forces of attraction
  • close together, fixed positions
  • regular lattice arrangement
  • definitive shape and volume
  • vibrate in fixed position, hotter= more vibration (solids expand)
30
Q

How do particles behave in a liquid?

A
  • Weak forces of attraction
  • Randomly arranged, free to move past each other (tend to stick closer together)
  • Definitive volume NOT shape
  • Constantly moving in random motion, hotter= more faster movement (liquid expands)
31
Q

How do particles behave in a gas?

A
  • Very weak forces of attraction
  • Free to move, far apart, travel in straight lines
  • NO definitive shape OR volume
  • Constantly moving in random motion, hotter= faster movement (gasses expand or pressure increases)
32
Q

What is Melting?

A

The change of state from a solid to a liquid

  • solid is heated, gains more energy
    -particles vibrate move, weakens the forces
  • melting point, enough energy, particles break free, turns to liquid
33
Q

What is Boiling?

A

The change of state from a liquid to a gas

  • Liquid is heated, particles gain more energy
  • Particles move faster, weakens + breaks bonds
  • Boiling point, enough energy to break bonds, becomes gas
34
Q

What does the amount of energy needed to change state depend on?

A

How strong the forces between particles are
- the stronger the forces, the more energy that is needed, the higher the melting + boiling temps

35
Q

What is Condensing?

A

The change of state from a gas to a liquid

  • gas cools, particles dont have enough energy to overcome forces of attraction
  • bonds form
  • boiling point, so many bonds have formed, gas becomes liquid, Condensing
36
Q

What is freezing?

A

The change of state from a liquid to a solid

  • Liquid cools, particles have less energy
  • not enough energy to overcome attraction, more bonds form
    -melting point, so many bonds form, particles held in place, become solid, Freezing.
37
Q

What are Nanoparticles?

A

Diameter between 1nm and 100nm

  • only contain a few 100 atoms
38
Q

What is nanoscience?

A

Science that investigates the uses and properties of nanoparticles

39
Q

What is the relationship between SA and Volume in Nanoparticles?

A

As the particles decrease in size (volume decreases), SA increases in relation to volume

SA:V ratio -> increases

  • less of a nanoparticle to work as an effective catalyst compared to products with billions of atoms rather than hundreds
40
Q

What are uses of Nanoparticles?

A
  • Catalysts -> large SA:V ratio
  • Nanomedicine -> fullerenes deliver drugs
  • Electrical circuits in computer chips -> conduct electricity
  • Cosmetics-> improve moisturiser without oiliness
  • Silver nanoparticles = antibacterial properties-> added to polymer fibres to make masks, deodorant etc
41
Q

What are the effects of Nanoparticles on health?

A
  • lack of investigation on effects (long term?), label products to show use of nanoparticles
  • Suncreams-> protect from UV, better coverage, may damage cells, may damage environment when washed away

Chemistry (13 decks)

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