Brainscape's Knowledge GenomeTM

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


See full index

IB Chemistry > Structure 2.1/2 The Ionic and Covalent Model > Flashcards

Structure 2.1/2 The Ionic and Covalent Model Flashcards

1
Q

What are ions?

A

Atoms or groups of atoms with an overall charge

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

How are ions formed?

A

Transfer of electrons from one atom to another, which results in both atoms having a full outer shell

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

What do metal atoms generally form in terms of ions?

A

Cations: positively charged ion

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

What do non-metal atoms generally form in terms of ions?

A

Anion: negatively charged ion

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

What are ionic compounds?

A

Compounds made up of a combination of cations and anions

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

What is ionic bonding?

A

Electrostatic attraction between ions of opposite charges

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

What are transition elements?

A

Elements whose atoms have incomplete d-subshells or who can give rise to cations with incomplete d subshells

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

What does isoelectronic mean?

A

Same amount of electrons

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

Which monatomic ions tend to possess the electron configuration of a noble gas?

A

Main group elements (not Group 14)

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

What is a polyatomic ion?

A

Overall charged unit of groups of joined atoms

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

What does the term ‘protonated’ mean?

A

Adding of a hydrogen ion (essentially just a proton)

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

What does the term deprotonated mean?

A

Removal of a hydrogen ion (essentially just a proton)

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

What is the empirical formulae?

A

Simplest ratio of atoms of each elements present in that compound

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

What form is the formula of an ionic compound written in?

A

Empirical formula

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

How to write an ionic compound?

A
  1. Name of positive ion (cation) first
  2. Include roman numerals if cation is a transition element
  3. Wirte name of anion (monatomic = ends with ‘ide’)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What do Roman numerals indicate on a transition metal?

A

Oxidation state (similar to charge on an ion) of metallic elements

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

What is an ionic lattice?

A

Regular, repeating 3-dimensional arrangement of cations and anions

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

How do ions arrange themselves in an ionic compound?

A

In the most stable configuration. Oppositely charged ions are as close together as possible. Ions of the same charge are as far apart as possible

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

What are the properties of ionic compounds?

A

Crystalline
Low volatilities
High melting and boiling points
Conduct electricity while molten or in aqueous solution (not when solid)
Some are soluble in water
Hard
Brittle

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

Why are ionic compounds crystalline?

A

Structure of lattice

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

What is the ionic radius?

A

In a crystalline ionic compound, it is the distance from the nucleus to the valence shell

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

What happens to the radius of an atom when it becomes a cation?

A

Reduces.
Loses a shell

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

What happens to the radius of an atom when it becomes an anion?

A

Enlarges.
Repel other electrons + swell atoms

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

What influences the structure of the ionic lattice?

A

Size of ionic radii
Charge of ions

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

What is volatility?

A

Measure of how readily a substance evaporates below its boiling point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Why do ionic compounds have high melting and boiling points?

A

Electrostatic attraction between charges is very strong. Large amounts of thermal energy are requried to separate ions

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

What is lattice enthalpy?

A

Energy needed to separate one mole of a solid ionic compound into gaseous ions under standard conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the formula for the lattice enthalpy of MgCl2?

A

MgCl2(s) -> Mg2+(g) + 2Cl-(g)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What units are lattice enthalpies measured in?

A

kJ / mol

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

What are endothermic reactions?

A

Processes that require energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are exothermic reactions?

A

processes that release energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What type of reaction is a lattice enthalpy?

A

Endothermic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the relationship between ionic charge and lattice enthalpy?

A

Greater charge on ion = stronger electrostatic attraction = higher lattice enthalpy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is the relationship between ionic radii and lattice enthalpy?

A

Larger ionic radii = greater separation of charges = weaker the electrostatic attraction = lower lattice enthalpy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is relationship between attractive force and theoretical lattice enthalpy?

A

Attractive force ∝ theoretical lattice enthalpy ∝ (charge on cation x charge on anion) / sum of ionic radii

36
Q

What is required for a substance to conduct electricity?

A

Free moving, charged particles

37
Q

Can solid ionic compounds conduct electricity?

A

No.
the ions are held rigidly in place within the lattice and are not free to move.

38
Q

Can molten/aqeuous solutions conduct electricity?

A

Yes. Ions are free to move towards electrodes of opposite charge

39
Q

What is the solubility of a substance?

A

Maximum amount of that substance that can be dissolved in a given quantity of solvent at a given temperature

40
Q

What is a saturated solution?

A

A solution where no more solute can be dissolved at that temperature

41
Q

In an insoluble substance, the energy required to separate the ions is much greater than?

A

The energy released when the ions become hydrated

42
Q

What happens when a soluble compound dissolves in water?

A

Ionic bonds within solid lattice are broken
Hydrogen bonds between adjacent water molecules are broken
ion-dipole bonds are formed between ions adn water molecules

Ions become hydrated (solvated by water molecules)

43
Q

If two aqeuous solutions are together and form a precipitate, what has been formed?

A

An insoluble solution

44
Q

Why are ionic compounds hard?

A

Strong electrostatic attraction between cations and anions causes crystals to resist change in shape + be hard

45
Q

Why are ionic compounds brittle?

A

IF sufficient force is applied to crystalline lattice
- rows of ions will move relative to one another
- ions of like charges will become adjacent
- adjacent ions of like charge will repel each other (causing lattice to shatter)

46
Q

What are covalent substances?

A

Formed when non-metallic elements join together

47
Q

What are some traits of colavent substances?

A

Solids/liquids/gases at room temperature

Can have low melting/boiling points

Generally poor conductors of electricity and heat

48
Q

What is a covalent bond?

A

A shared pair of electrons

49
Q

How do non-metals bond together?

A

sharing one or more pairs of electrons

50
Q

What bonds two non-metals together?

A

Electrostatic attraction of two nuclei towards shared pair of electrons

51
Q

What happens if two atom nuclei are too far apart?

A

no attraction

52
Q

What does the optimal bond length involve?

A

Maximising attraction between the two positive nuclei to the shared pair of negative electrons while minimising the repulsion between two positive nuclei

53
Q

What can covalent bonds form between?

A

discrete molecules
large molecules
covalent networks

54
Q

What are discrete covalent molecules?

A

small groups of atoms held together by strong covalent bonds

55
Q

What do covalent bonds between large numbers of atoms form?

A

Large molecules such as polymers, plastics, fullerenes

56
Q

What do covalent bonds between an infinite number of atoms form?

A

Covalent networks such as graphite, diamond, silicon, etc

57
Q

What is the octet rule?

A

Tendency of atoms to achieve a full valence shell with a total of 8 electrons

58
Q

What do Lewis formulas show?

A

All valence electrons
- bonding pairs
- non-bonding pairs

59
Q

How to draw Lewis formulas of molecules and ions?

A
  1. Add up total number of valence electrons (including charges)
  2. Write atoms in order bonded
    - non-metal atom (with the lowest electronegativity = most top right of table) that forms most bonds will usually be central atom
  3. Place single covalent bonds betweeen atoms
  4. Place non-bonding electrons to the non-central atoms so that each has an octet of electrons
  5. Place any remaining on central atom
  6. Use lone pairs on non-central atoms to form double/triple bonds to ensure the central atom has an octet
  7. Draw square brackets around Lewis formula and write overall charger outside brackets at top right corner if polyatomic
60
Q

How to find element with lowest electronegativity via a periodic table?

A

Most to right

61
Q

What is the relationship between bond strength and amount of bonds?

A

More bonds (i.e. triple covalent bond) = stronger

62
Q

What is the relationship between bond strength and amount of bonds?

A

More bonds = stronger bond

63
Q

What does VSEPR stand for?

A

Valence
Shell
Electron
Pair
Repulsion

64
Q

What does the VSEPR model enable?

A

The shape of the molecules to be predited from the repulsion of electron domains around a central atom

65
Q

What is an electron domain?

A

region where electrons are likely to be found

66
Q

What can each electron domain be occupied by?

A

A single electron
Lone pair
Single bond
Double bond
Triple bond

67
Q

How are electron domains orientated?

A

As far away as possible from each other in 3D space

68
Q

What are the three electron domain geometry options?

A

Linear
Trigonal planar
Tetrahedral

69
Q

What are thre five molecular geometry options?

A

Linear
V-shaped
Trigonal planar
Trigonal pyramidal
Tetrahedral

70
Q

What is the electron domain geometry of a central atom surrounded by 4 occupied electron domains?

A

Tetrahedral

71
Q

What is the electron domain geometry of a central atom surrounded by 3 occupied electron domains?

A

Trigonal planar

72
Q

What is the electron domain geometry of a central atom surrounded by 2 occupied electron domains?

73
Q

What is the molecular geometry of a central atom surrounded by 4 occupied electron domains and 0 lone pairs?

A

Tetrahedral
109.5 degree bond angle

74
Q

What is the molecular geometry of a central atom surrounded by 4 occupied electron domains and 1 lone pairs?

A

Trigonal pyramidal
107 degree bond angle

75
Q

What is the molecular geometry of a central atom surrounded by 4 occupied electron domains and 2 lone pairs?

A

Bent
105 degree

76
Q

What is the molecular geometry of a central atom surrounded by 4 occupied electron domains and 3 lone pairs?

77
Q

What is the molecular geometry of a central atom surrounded by 3 occupied electron domains and 0 lone pairs?

A

trigonal planar

78
Q

What is the molecular geometry of a central atom surrounded by 3 occupied electron domains and 1 lone pairs?

79
Q

What is the molecular geometry of a central atom surrounded by 3 occupied electron domains and 2 lone pairs?

80
Q

What is the molecular geometry of a central atom surrounded by 2 occupied electron domains and 0 lone pairs?

A

Linear
180 degrees

81
Q

What is the molecular geometry of a central atom surrounded by 2 occupied electron domains and 1 lone pairs?

82
Q

What is the molecular formula?

A

The actual number of atoms of each element present in a covalent molecular substance

83
Q

What is the order of repulsion in terms of bonding pairs and lone pairs?

A

Least repulsed: bonding pair + bonding pair

Middle repulsed: bonding pair + lone pair

Most repulsed: lone pair + lone pair

84
Q

What is a coordination bond?

A

Covalent bond in which both the electrons of the shared pair originate from the same atom?

85
Q

How is ammonium formed?

A

NH3(aq) + H+(aq) -> NH4+ (aq)

86
Q

How to know if a coordinate bond has occured?

A

One atom will have formed more bonds that usual

IB Chemistry (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions