Brainscape's Knowledge GenomeTM

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


See full index

Science > Chemical Bonding Part 2 > Flashcards

Chemical Bonding Part 2 Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

When the covalent bond is polar? (2)

A

The molecule is either polar or non polar

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

What determines whether it is polar or non polar? (1)

A

Shape of the molecule

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

What is the polarity of a molecule? (1)

A
  • Sum of all bond polarities
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

If the diatomic molecule is polar…

There will be what? (1)

A

An Electronegativity difference

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

If the molecule is not diatomic…

What can tell you the molecule is polar or non polar? (1)

A

The shape of the molecule

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

Properties of:

WATER - H2O (4)

A
  • Angular
  • Therefore not symmetrical (no sides cancel)
  • H-O bond polar covalent
  • Therefore polar molecule
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Properties of:

AMMONIA - NH3 (4)

A
  • Pyramidal
  • Therefore not symmetrical
  • N-H bond polar covalent
  • Therefore molecule is polar
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Properties of:

CARBON DIOXIDE - CO2 (4)

A
  • Linear shape
  • Symmetrical (bonds cancel)
  • Therefore molecule is non polar
  • C-O bond polar covalent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Properties of:

SULPHUR DIOXIDE - SO4 (4)

A
  • Bent shape
  • Therefore not symmetrical (sides don’t cancel)
  • S-O bond polar covalent
  • Therefore polar molecule
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Properties of:

METHANE - CH4 (4)

A
  • Tetrahedral
  • Symmetrical (bonds cancel)
  • Therefore molecule is non polar
  • C-H bond polar covalent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Properties of:

CARBON TETRACHLORIDE - CCl4 (4)

A
  • Tetrahedral
  • Symmetrical (bonds cancel)
  • Therefore molecule is non polar
  • C-Cl bond polar covalent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

All halogens will give what? (2)

A
  • A symmetrical molecule

- Therefore non polar molecule

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

Is oil polar or non polar? (1)

A

Non polar

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

What is an Intramolecular force? (2)

A
  • Intramolecular forces are forces inside the molecule keeping compounds together
  • Namely in covalent bonding
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is an Intermolecular force (2)

A

An intermolecular force is a weak force of attraction between molecules or between atoms of noble gas

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

Intra & Inter
WATER
(3x3)

A

Intramolecular

  • H-O attraction
  • X25 strong than Inter
  • 464 KJ/mol to break down

Intermolecular

  • H2O to H2O attraction
  • Not as strong as Intra
  • 19 KJ/mol to break down
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the breaking down of molecular forces known as? (1)

A

Sublimation

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

Give 4 examples of what strength influences in a molecule? (4)

A
  • Shape
  • Volume
  • Surface Tension
  • Ability to flow
  • Rate of evaporation
  • Melting and boiling points
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

The stronger the intermolecular force… (2)

A

The greater the amount of energy needed to move molecules apart

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

Van Der Waals forces are weaker than… (2)

A
  • Chemical bonds
    Lower melting points
  • Intramolecular forces
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Noble gases do not…? (2)

A
  • Bond with other elements

- Held together by London Forces

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

Dipole - Dipole? (3)

A
  • Positive and Negative poles in the molecule
  • Weaker than Ionic and Metallic
  • Molecules must be almost touching or touching
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Example of Dipole - Dipole? (3)

A

HCl

  • Attraction relatively weak
  • Cl-H X130 more strong than HCl–HCl
  • Boiling point is -85°C
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Dipole - Induced Dipole? (3)

A
  • Created by disturbing the arrangement of the electrons
  • weaker than dipole - dipole
  • Stronger than London forces
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Example of Dipole - Induced Dipole? (2)

A

H-Cl – Ar

  • H-Cl is dipolar
  • Ar is non polar
  • dipole induces a temporary dipole in Argon
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which non polar gases create a Dipole - Induced Dipole molecule? (2)

A

O2 & CO2

- Dissolve sparingly into water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Different names for London Forces (3$

A
  • Momentary Dipole Forces
  • Induced Dipole - Induced Dipole
  • Dispersion Forces
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

London Forces? (3)

A
  • Weakest of the Van Der Waals Forces
  • Temporary attractive force
  • Causes non polar substances to
    :: condense into liquids and
    :: freeze into solids when the temperature is lowered
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

London forces exist between? (2)

A
  • 2 Non Polar Molecules

- Atoms of noble gases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

The bigger the molecule… (2)

Intermolecular

A
  • Heavier

- Stronger the forces

31
Q

The bigger the atom… (2)

A
  • The further the valence electrons are from the nuclei

- Still strong enough forces to be SOLID or LIQUID at room temperature

32
Q

The attraction between Helium atoms. (4)

A
  • Helium liquid at room temperature below 4K
  • Forces of attraction between neutral atoms, increases as atoms get closer
  • Helium atom is perfectly symmetrical
  • BUT movement of the electrons around the NUCLEI can cause electron distribution = A momentary dipole
33
Q

Van Der Waals strength determined by… (2)

A
  • Number of electrons (size of electron cloud) surrounding the molecule which increases with molecular mass
  • The surface area (size) of the molecule
34
Q

Larger the molecule… (2)

Smaller the molecule… (2)

A
  • Easier it is to redistribute and form
  • Easier polarized
  • Harder to polarize
  • Electrons close to the nucleus
35
Q

Overtime non polar molecules have…? (1)

However…? (2)

A
  • Symmetrical distribution of electrons
  • There is a probability that the electron density has shifted
  • Creates a brief POLARIZATION of charge or a TEMPORARY DIPOLE
36
Q

The strength of the Van Der Waal forces determines…? (2)

A
  • How easily the electron cloud can be polarized

- MOLECULAR MASS + , INTERMOLECULAR FORCE +

37
Q

5 point on Intermolecular forces and molecules (5)

A
  • Bigger molecules = bigger electron clouds
  • Makes them more easily polarized
  • Form stronger dipoles
  • Therefore stronger intermolecular forces
  • Takes more energy to break the stronger bond
38
Q

CH4 compared to C2H6?

Stronger? Bigger? Etc. (4)

A

C2H6

  • Stronger
  • Molecule is bigger
  • Higher boiling point
  • More energy required to overcome force of attraction
39
Q

When the covalent bond is non polar (1)

A

The molecule is non polar

40
Q

What is a Hydrogen bonding is very polar, why? (6)

A
  • An attractive force between a hydrogen atom and a covalently bonded small, very electronegative atom such as
  • N, O, F
  • Top groups of 5:6:7
  • Electrons spend a lot of time around these elements.
  • Therefore hydrogen nucleus exposed = Substantial
    NH3, H2O, H-F
41
Q

Why is Water not a gas at room temperature? (2)

A
  • Abnormally high boiling point

- Small molecule weight

42
Q

Capital Delta shows? (1)

A

Strong forces

43
Q

Hydrogen bonded with Water is responsible for… (3)

A
  • High surface tension
  • Heat of evaporation high
  • Solid phase less dense than liquid phase
44
Q

Hydrogen compared to covalent? (1)

A

1/10 the strength

45
Q

Hydrogen bonding responsible for… (3)

A
  • Genes in the DNA molecule
  • Hylical structure of protein
  • incredible strength of KEVLAR (Canoe hulls & bullet proof vests)
46
Q

Why does H2O have a higher boiling point thank H2S?

Same hydrides of group 6? (2)

A
  • H2O involves hydrogen bonding
  • Very strong bond, require more energy to break than H2S
  • Therefore higher boiling point
47
Q

Explain why H2S has a higher boiling point than H2Se? (5)

A
  • H2Se is a bigger molecule
  • Electron clouds more easily polarized
  • Stronger intermolecular forces
  • Therefore more energy required to break the bond
  • Therefore higher boiling point
48
Q

Non metals are… than metals (1)

A

More electronegative

49
Q

What happens during Ionic bonding? (5)

A
  • Difference greater than 2,1 in Electronegativity
  • Between metal and a non metal
  • Non metal pulls electrons so strongly they completely leave the metal
  • 2 oppositely charged Ions - Coulombic charges
  • Held together by ELECTROSTATIC RADIATION
50
Q

Ionic bonding forms? (2)

A
  • Salts

- Ionic substances

51
Q

When does Ionic bonding occur? (5)

A
  • When non metals bond with metals
  • Metal loses electrons, becomes + ion (cation)
  • Non metal gains electrons, becomes - ion (anion)
  • 2 ions attract each other by an Electrostatic force
  • Ions pack together in a crystal lattice
52
Q

What is an Ionic bond? (2)

A

An Ionic bond forms due o the transfer of electrons and subsequent electrostatic attraction

53
Q

What is a crystal lattice? (2)

A

A crystal lattice is a regular three-dimensional structure of particles

54
Q

What is a Metallic bond? (2)

A

A metallic bond is between a positive kernel and a sea of de localized electrons

55
Q

What do metals tend to have? (1-5)

A 
High Melting & Boiling Point
- Therefore forms strong bonds
- High in density 
\: electrons packed close together
\: Outer orbitals overlap
\: Valence electrons become DELOCALIZED
56
Q

Metals are held together by… (2)

A

Strong forces of attraction between
+ Nuclei
- delocalized electrons

57
Q

Why can metals conduct a current? (2)

A
  • Sea of delocalized electrons

- That can move

58
Q

Ion - Dipole? (4)

A
  • Attractive force
  • Electrostatic attraction
    # Ionic compounds in Polar Liquids
    NaCl in H2O
59
Q

Ion - Induced Dipole (4)

A
  • Weak attraction
  • By disturbing the arrangement of the electrons in Non Polar
    # Ionic compounds in Non Polar Liquids
    Fe and O2
60
Q

Simple small molecule has… (1)

Give 4 examples? (4)

A
  • Few atoms
  • O2 Oxygen
  • H2O Water
  • C18H18 Petrol
  • C12H22O11 Sugar
61
Q

A giant molecule has… (1)
Also known as… (1)
Examples? (4)

A
  • Millions of atoms per molecule
  • Macromolecule
  • Diamond, Graphite, Silicon Dioxide, Sodium Chloride
62
Q

Giant molecules are. (3)

A
  • Some of the hardest structures known
  • Strong bonds between their atoms
  • High melting & boiling points
63
Q

What are Allotropes? (4)

A
  • Different forms of the same element
  • Different bonding arrangements between atoms
  • Result in different structures w/ chemical and physical properties
  • Diamond, Graphite & Charcoal : Allotropes of Carbon
64
Q

Diamond? (6)

A
  • Single giant molecule
  • Made up of endless strong covalent bonds between C atom
  • Each C atom covalently bonded to 4 other C atoms
  • Why it is the hardest natural substance
  • Very high melting point : 3550°C
  • No free electrons : Excellent insulator
65
Q

Graphite? (6)

A
  • Made up of carbon atoms
  • Each C atom valency bonded to 3 other C atoms
  • Link up, form 6 membered rings : form planes U flat sheets of C
  • 4th electron of each carbon : not bonded : becomes delocalized
  • Delocalized electrons can conduct an electric current
  • Used to make electrodes (during electrolysis)
66
Q

Planes and Flat Sheets in Graphite? (7)

A
  • Covalent bonding between C atoms in planes is : STRONG
  • Flat sheets of C lie on top of each other
  • Held together by weak forces of attraction (London)
  • Spacing between bigger than diameter of the individual atom
  • Forces weak : sheets easily slide past each other
  • Sliding sheets give graphite its softness
  • for Writing and Lubricating properties
67
Q

Sodium Chloride? (2)

A
  • Giant molecule

- Ionic bonding

68
Q

SOLID Sodium Chloride? (4)

A
  • Ions held very close together
  • With very strong forces
  • Are unable to move apart
  • Therefore cannot conduct and electric current (NaCl)
69
Q

Solid NaCl added to Water? (5)

A
  • Ions can separate : Dissociate
  • Move freely throughout water
  • Ions become surrounded by polar water molecules
  • ION - DIPOLE force of attraction
  • Aqueous solution = Conducts an electric current
70
Q

Molten NaCl? (2)

A
  • Ions able to move

- Conducts electricity in a liquid phase

71
Q

For a substance to conduct an electric current ? (2)

A
  • Charged particles must be able to move

- Charged particles can be +, -, or - ions

72
Q

Silicon Dioxide? (7)

A
  • Giant covalent molecule
  • Each Si-O bond is a single bond
  • Each Si bonds with 4 Oxygen Atoms

High melting point : 1700°C : Si-O bonds must be broken before melting

Hard

Doesn’t conduct electricity : No delocalized electrons

Insoluble in : water and organic solvents

73
Q

Ionic solids don’t conduct but Ionic liquids do? (2)

A

Liquids have a charge that’s free to move
Solids are locked in the crystal
Ions flow in liquid not in a fixed position
Electric currents created by delocalized electrons

74
Q

Solutions of Ionic solids don’t conduct an electric current?

A

No delocalized electrons?

Science (4 decks)

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