Brainscape's Knowledge GenomeTM

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


See full index

A level Chemistry > Unit 1.4 - Bonding > Flashcards

Unit 1.4 - Bonding Flashcards

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

What are the two types that chemical bonding can be divided into?

A

Intramolecular bonding
Intermolular bonding

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

Intramolecular bonding

A

Bonds that form within the molecule - they hold atoms in place

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

What are the bonds that form within a molecule?

A

Intramolecular bonding

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

What are the bonds that hold atoms in place?

A

Intramolecular bonding

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

Intermolecular bonding

A

Bonds formed between molecules

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

What are the bonds formed between molecules?

A

Intermolecular bonding

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

Give an example of intermolecular bonding

A

Hydrogen bonding

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

What is hydrogen bonding an example of?

A

Intermolecular bonding

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

Which type of bonding is stronger - Intramolecular or intermolecular?

A

Intramolecular

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

Energy per mole of bonds for Intramolecular bonds

A

100 - 1000kJ per mole of bonds

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

What are Intramolecular bonds responsible for within the molecule?

A

The chemical reactivity of the molecule

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

What are the intermolecular bonds responsible for in a molecule?

A

The physical properties of the molecule

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

What type of bonds are responsible for the chemical reactivity of a molecule?

A

Intramolecular bonds

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

What type of bonds are responsible for the physical properties of a molecule?

A

Intermolecular bonds

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

How can the chemical reactivity of a molecule be observed?

A

In a chemical reaction

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

What can be observed of a molecule during a chemical reaction?

A

Its chemical reactivity

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

What are physical properties?

A

Properties that can be observed or measured without changing the identity of the substance

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

Name some physical properties

A

Melting point
Boiling point
Solubility

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

Under which type of bonds do ionic, covalent and coordinate bonds fall?

A

Intramolecular bonds

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

Name 3 Intramolecular bonds

A

Ionic bonds
Covalent bonds
Coordinate bonds

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

Ionic bonds

A

A bond formed by the electrical attraction between positive and negative ions (cations and anions)

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

A bond formed by the electrical attraction between positive and negative ions (cations and anions)

A

Ionic bond

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

Covalent bonds

A

Has a pair of electrons with opposed spin shared between 2 atoms with each one giving 1 electron

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

Has a pair of electrons with opposed spin shared between 2 atoms with each one giving 1 electron

A

Covalent bonds

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

Coordinate bond

A

A covalent bond in which both of the shared pair of electrons come from 1 of the atoms

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

A covalent bond in which both electrons come from 1 of the atoms

A

Coordinate bond

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

When do ions form?

A

When atoms gain or lose electrons by electron transfer

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

When does the process of forming ions stop?

A

When the atom which loses and the one which gains an electron have stable electronic structures

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

Describe the charges on two ions formed during electron transfer

A

Opposite charges

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

What forms when atoms gain or lose electrons?

A

Ions

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

What usually loses an electron to what during ionic bonding?

A

Metals to non-metals

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

What do metals form during ionic bonding?

A

Positive ions (cations)

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

What form positive ions (cations) during ionic bonding?

A

Metals

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

What do non-metals form during ionic bonding?

A

Negative ions (anions)

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

What form negative ions (anions) during ionic bonding?

A

Non-metals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Cations

A

Positive ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Positive ions

A

Cations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Negative ions

A

Anions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Anions

A

Negative ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What IS the ionic bond during ionic bonding?

A

The electrostatic force of attraction between 2 ions of opposite charge

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Which rule do we follow for ionic bonding and what does this mean?

A

The octet rule - 8 electrons in the outer shell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What do we use to show ionic bonding?

A

Dot-cross notation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is the charge on an in equal to?

A

The amount of electrons gained or lost by the atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What do many elements form ions which have the same electronic configuration as?

A

Noble gases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What do atoms do during covalent bonding?

A

Share electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What type of bonding involves atoms sharing electrons?

A

Covalent bonding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What does a single covalent bond contain?

A

Two electrons, one from each atom, shared between them with opposite spins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What do the electrons in a covalent bond have?

A

Opposite spins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

How many electrons are shared in a double covalent bond?

A

4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

How many electrons are shared in a triple covalent bond?

A

6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What type of bonding involves two electrons shared?

A

Single covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What type of bonding involves 4 electrons shared?

A

Double covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What type of bonding involves 6 electrons shared?

A

Triple covalent bonding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What type of elements usually for covalent bonds?

A

Non-metals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What do non-metals usually form?

A

Covalent bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

When does covalent bonding come to an end?

A

When both atoms have stable electronic configurations (the same as a noble gas)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What IS a covalent bond?

A

An electrostatic force of attraction between the 2 nuclei and the shared electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What’s stronger - a covalent or an ionic bond?

A

Covalent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

How is a single covalent bond demonstrated?

A

—

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What does — represent?

A

A single covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

How is a double covalent bond shown?

A

==

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What does == demonstrate?

A

A double covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

What’s the name for the electrons not used in bonding?

A

Lone electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

Lone electrons

A

Electrons not used in bonding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

Describe triple covalent bonds - which elements has these?

A

Nitrogen - they’re strong bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Why is nitrogen an unreactive gas?

A

It has strong triple covalent bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What do triple covalent bonds in nitrogen cause it to be? Why?

A

Unreactive, as this is a strong bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

What is added to crisp packets and why?

A

Nitrogen, as it’s an Unreactive gas due to its strong triple covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Give a use for nitrogen and explain why

A

In crisp packets, as it’s an Unreactive gas so it keeps them crisp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

What’s another word for coordinate bonds?

A

Dative bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

What are dative bonds?

A

Coordinate bonds (old word for it)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

What are coordinate bonds a type of?

A

Covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

Where do the electrons come from for coordinate bonds?

A

Both electrons are supplied by 1 atom

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

Where does a coordinate bond form between 2 atoms?

A

Between an atom which has a lone pair or electrons and another atom which is electron deficient (i.e - has an empty orbital)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

Electron deficient

A

Has an empty orbital

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

What is an atom which has an empty orbital?

A

Electron deficient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

What forms between an atom with a lone pair of electrons and another which is electron deficient?

A

A coordinate bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

Give 3 examples of coordinate bonds forming

A

-between ammonia + boron trifluoride
-hydrated proton (H30+)
-ammonia ion (NH4+)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

What do the following all form?
-ammonia and boron trifluoride
-hydrated proton (H30+)
-ammonia ion (NH4+)

A

Coordinate bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

Which element can expand its octet rule during ionic bonding and what to?

A

P, to 10 electrons in the outer shell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What type of compound is sodium chloride?

A

Ionic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

What shape ions do sodium and chlorine have?

A

Nearly spherical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

Name 2 ions which have a nearly spherical shape?

A

Sodium and chlorine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

What’s special about a spherical ion?

A

Uniform electric field around it - can attract ions of opposite charge in all directions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

What type of ions have a uniform electrical field around them and can attract ions of opposite charge in all directions?

A

Spherical ions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
86
Q

What can an ionic bond be classed as and why?

A

Non-directional as it can attract ions of opposite charge in all directions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
87
Q

What type of bond is non-directional and why?

A

Ionic as it can attract ions of opposite charge in all directions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
88
Q

Even though ionic bonds are non-directional bonds, what do we have to consider? Why?

A

Due to the number of ions being very large, we have to consider repulsion between ions of the same charge and attraction forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
89
Q

What occurs between ions of the same charge?

A

Repulsion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
90
Q

What do repulsion and attraction forces do?

A

Restrict the number of ions of opposite charge which can pack around an ion and the positions which the ions can occupy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
91
Q

Restrict the number of ions of opposite charge which can pack around an ion and the positions which the ions can occupy

A

Repulsion and attraction forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
92
Q

When are there many repulsion and attraction forces to consider?

A

When the number of ions is very large

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
93
Q

How do ions pack and what does this mean?

A

A lattice arrangement - there’s an equilibrium between the attractive and the repulsive forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
94
Q

Lattice arrangement

A

Equilibrium between the attractive forces and repulsive forces (ions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
95
Q

What does ions lattice arrangement depend on?

A

The charges on the two ions and their relative sizes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
96
Q

What do the charges on two ions and their relative sizes affect?

A

The lattice arrangement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
97
Q

Why are chlorine ions larger on the sodium chloride lattice?

A

Due to a larger atomic radius (extra shell of 8 electrons)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
98
Q

What’s strongest - ionic or covalent bonds?

A

Covalent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
99
Q

What’s an example of covalent bonds being the strongest?

A

Carbon has a giant covalent structure, and has the highest melting point of all

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
100
Q

Which element has the highest melting point and why?

A

Carbon due to its giant covalent structure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
101
Q

What does Carbon’s giant covalent structure give it?

A

The highest melting point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
102
Q

Where is most of electron density centred?

A

Around nuclei

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
103
Q

What is mostly centred in the nuclei?

A

Electron density

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
104
Q

What IS a covalent bond?

A

Attractive force between the positive nuclei and the negative charge cloud of the shared electron pair

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
105
Q

Attractive force between the positive nuclei and the negative charge cloud of the shared electron pair

A

Covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
106
Q

Where are the shared electrons in a covalent bond?

A

Between the nuclei

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
107
Q

What’s the net affect of the shared electrons being between the 2 nuclei in a covalent molecule?

A

The net effect of the attractive forces between the electrons and the nuclei is to hold the 2 nuclei together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
108
Q

What holds two nuclei together in a covalent molecule?

A

The net effect of the attractive forces between the electrons and the nuclei is to hold the 2 nuclei together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
109
Q

Repulsive forces between ions

A

Forces between inner shells of electrons on each atom
Forces between the positive charges on nuclei
Forces between inner shells of electrons and charge cloud of the bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
110
Q

What determine a bond’s length?

A

The balance between the attractive and repulsive forces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
111
Q

What do the balance between the attractive and repulsive forces determine?

A

The bond length

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
112
Q

Under which conditions do metals easily lose up to 3 outer electrons?

A

As long as there’s a non-metal available to form an ionic bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
113
Q

What 2 types of elements for ionic bonds?

A

Metal with a non-metal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
114
Q

What does a metal with up to 3 outer electrons do if there’s no non-metal present?

A

Merge the outer main levels of all of its atoms so that electrons are no longer associated with any 1 atom, but are shared between all of them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
115
Q

What type of bond occurs when atoms merge their outer main levels so that electrons are associated with all atoms?

A

Metallic bonding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
116
Q

What does 2 atoms merging their outer main levels together form?

A

A sea of electrons, or a pool of delocalised/valence electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
117
Q

When does a pool of delocalised/valence electrons form?

A

When metals merge the outer main levels of their atoms when there’s no non-metal available for ionic bonding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
118
Q

A pool of..what type of electrons? (Metals merging their outer main levels of atoms)

A

Delocalised/valence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
119
Q

How are the “sea” of electrons and the metal atoms charged?

A

Sea = negative
Metal atoms = positice

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
120
Q

What IS a metallic bond?

A

The attraction between the negatively charged “sea” of electrons and the positive metal atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
121
Q

The attraction between the negatively charged “sea” of electrons and the positive metal atoms

A

Metallic bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
122
Q

What can metals do well and why?

A

Conduct electricity and heat (delocalised electrons can carry a current)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
123
Q

What type of materials can conduct electricity and heat well and why?

A

Metals due to the delocalised electrons being able to carry a current

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
124
Q

What does more delocalised electrons mean for a metal?

A

Higher melting point and a better conductor of electricity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
125
Q

What makes a metal a better conductor of electricity and gives it a higher melting point?

A

Having more valence electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
126
Q

What decides how many delocalised electrons a metal has?

A

How many electrons the atom can lose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
127
Q

What does how many electrons a metal atom can lose affect?

A

The amount of delocalised electrons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
128
Q

What happens to melting and boiling points across the period and why?

A

Increase
Ionic charge increases
Ionic size decreases
Number of outer shell electrons increases
Attraction increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
129
Q

Electronegativity

A

The ability of an atom to attract a pair of electrons to itself in a covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
130
Q

The ability of an atom to attract a pair of electrons to itself in a covalent bond

A

Electronegativity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
131
Q

What are the most electronegative elemtents?

A

N, O and F (F is most)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
132
Q

What’s the electronegativity of all noble gases and why?

A

0
Cannot accept electrons de to a full outer shell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
133
Q

Which elements have an electronegativity value of 0 and why?

A

Noble gases as they cannot accept electrons due to a full outer shell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
134
Q

Electronegativity trend across a period + explanation

A

Increases (increased nuclear charge)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
135
Q

Electronegativity trend down a group + explanation

A

Decreases (increased screening)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
136
Q

What type of elements have low Electronegativity values?

A

Metals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
137
Q

What type of elements have high electronegativity values?

A

Non-metals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
138
Q

Describe the electronegativity values of the elements in the middle of the periodic table

A

Intermediate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
139
Q

What is electronegativity measured on?

A

A Pauling scale

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
140
Q

What ca electronegativity determine?

A

The type of bond that will be formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
141
Q

What determines the type of bond that will be formed?

A

Electronegativity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
142
Q

The greater the difference in electronegativity…

A

…the more ionic the character of the bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
143
Q

What makes the character of a bond more ionic?

A

Greater difference in electronegativity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
144
Q

Which two elements have the biggest difference in electronegativity and what does this mean?

A

Potassium and fluorine - they form the most ionic bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
145
Q

What do many ionic bonds have?

A

Covalent character

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
146
Q

What type of bond is an ionic bond if it has covalent character?

A

Polar covalent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
147
Q

Polar covalent bond

A

Ionic bond with covalent character

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
148
Q

What type of bond is between 2 identical species? Why?

A

Non-polar covalent - there’s no difference in electonegativity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
149
Q

What do non-polar covalent bonds occur in and why?

A

Two identical species as there’s no difference in electronegativity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
150
Q

What type of bond ones no difference in electronegativity lead to?

A

Non-polar covalent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
151
Q

Where is the electron pair in a polar covalent bond?

A

Isn’t always situated exactly between the 2 atoms - it’s pulled towards the more electronegative one in a covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
152
Q

In what type of bond is the electron pair not situated exactly equally between 2 atoms?

A

Polar covalent bond - pulled towards the more electronegative one in a polar bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
153
Q

What’s caused in a polar bond?

A

Difference in electronegativity causes a permanent dipole

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
154
Q

What causes a permanent dipole?

A

The difference in electronegativity in a polar bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
155
Q

What does a greater difference in electronegativity mean for a bond?

A

More polar bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
156
Q

What makes a bond more polar?

A

Greater difference in electronegativity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
157
Q

Describe the atoms in a non-polar covalent bond?

A

The two atoms are the same, so they have equal electronegativity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
158
Q

Where is the electron pair in a non-polar covalent bond? Why?

A

Shared equally between the two atoms as they’re the same and have equal electronegatives

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
159
Q

What type of bond has the electron pair shared equally and why?

A

Non-polar due to the atoms being the same, so they have equal electronegativity

160
Q

What moves towards the more electronegative element?

A

Electron densiy

161
Q

Where does electron density move?

A

Towards the more electronegative element

162
Q

What do we have if ALL of the electron density is by one element?

A

Exclusive + and - charges (ionic bond)

163
Q

In what type of bond do we have exclusive + and - charges?

A

Ionic bond

164
Q

Where is the electron density in an ionic bond?

A

All next to the more electronegative element

165
Q

Where is electron density in a polar covalent bond?

A

Towards the more electronegative element

166
Q

What type of bond is formed when the electron density is towards the more electronegative element?

A

Polar covalent bond

167
Q

Draw an electron density diagram presenting a non-polar covalent bond

A

(Check notes)

168
Q

Draw an electron density diagram presenting a polar covalent bond

A

(Check notes)

169
Q

Draw an electron density diagram presenting an ionic bond

A

(Check notes)

170
Q

In the electron density diagram for what type of bond would it be distorted towards the electronegative end?

A

Polar covalent bond

171
Q

In what type of electron density diagram are the electronegatives equal?

A

Non-polar covalent bond

172
Q

In what type of electron density diagram do we have exclude + and -?

A

Ionic bond

173
Q

What does a very large difference in electronegativity mean?

A

Fully ionic bond (higher % ionic character)

174
Q

Do ionic bonds show some covalent character?

A

Yes

175
Q

What character do ionic bonds still show?

A

Some covalent character

176
Q

Polarisation of ions

A

When small positive ions (cations) pull electron density off neighbouring ions due to some covalent character

177
Q

When small positive ions (cations) pull electron density off neighbouring ions due to some covalent character

A

Polarisation of ions

178
Q

When is polarisation of ions easier?

A

If the anion is large and has a high negative charge

179
Q

Which process is easier is an anion is large and has a high negative charge?

A

Polarisation of ions

180
Q

What pull electron density off of neighbouring ions during the polarisation of ions?

A

Small positive ions (cations)

181
Q

What happens eventually during polarisation of ions?

A

Electrons become shared and the bond increased in covalent character

182
Q

In which process do bonds increase in covalent character?

A

Polarisation of ions

183
Q

What do cations pull away and from what during polarisation of ions?

A

Electron density off neighbouring ions

184
Q

Draw an ionic bond with some covalent character

A

(Check notes)

185
Q

Draw an ionic bond with substantial covalent character

A

(Check notes)

186
Q

In general, what value of electronegativity difference forms non-polar covalent bonds?

A

Less than 0.4

187
Q

What does an electronegativity difference of less than 0.4 generally show?

A

A non-polar covalent bond

188
Q

Generally, what do electronegativity differences between 0.4 and 18 show?

A

Polar covalent bond

189
Q

What value for the difference in electronegativity generally represents a polar covalent bond?

A

0.4 - 1.8

190
Q

What does an electronegativity of more than 1.9 generally represent?

A

Ionic bond

191
Q

What difference in electronegativity implies an ionic bond?

A

1.9+

192
Q

Which forces explain physical properties of covalent molecules?

A

Intermolecular forces

193
Q

What properties do intermolecular forces explain and in what?

A

Physical properties of covalent molecules

194
Q

Name 2 Van der Waal forces

A

Induced dipole-induced dipole forces
Dipole-dipole forces

195
Q

What are induced-dipole induced-dipole and dipole-dipole forces examples of?

A

Van der Waal forces

196
Q

What’s the weakest Van der Waal force?

A

Induced dipole-induced dipole force

197
Q

What creates a higher boiling point?

A

Larger molecule
More electrons
Stronger intermolecular forces

198
Q

How do the quantity of electrons reflect on the strength of the intermolecular forces in a compound?

A

More electrons = stronger intermolecular forces

199
Q

Can each halogen be liquified? Why is this strange?

A

Yes, even though the covalent bond between the molecules is non-polar

200
Q

What does a stronger attraction between electrons lead to?

A

Higher melting points

201
Q

Why do larger molecules lead to higher boiling points?

A

More electrons
Greater fluctuation in the electron cloud
Larger dipoles
Stronger attraction

202
Q

What forms a stronger attraction in terms of dipoles?

A

Larger dipoles = stronger attractions

203
Q

What causes a larger dipole?

A

A greater fluctuation in the electron cloud due to more electrons

204
Q

What is a greater fluctuation in the electron cloud caused by and what does this lead do?

A

More electrons
Larger dipoles

205
Q

How can non-polar covalent bonds form temporary dipoles?

A

At any instant, the distribution is not equal with the electrons being more under the influence of 1 atom due to constant movements of electrons in the atom

206
Q

Why is the distribution of electrons in a non-polar covalent bond not always equal?

A

Constant movements of the electrons in an atom

207
Q

What does the constant movements of electrons in an atom lead to?

A

Non-polar covalently bonded molecules forming temporary dipoles

208
Q

Draw the temporary dipole between iodine molecules with a non-polar covalent bond

A

(Check notes)

209
Q

When can a halogen (with a non-polar covalent bond) be liquified?

A

When forming temporary dipoles through induced dipole-induced dipole forces

210
Q

What can a temporary dipole do to another temporary dipole in a nearby molecule?

A

Induce it to cause a force of attraction between them

211
Q

Induced dipole - induced dipole force

A

When a temporary dipole induces another temporary dipole in a nearby molecule, causing a force of attraction between them

212
Q

When a temporary dipole induces another temporary dipole in a nearby molecule, causing a force of attraction between them

A

Induced dipole - induced dipole force

213
Q

What type of molecules do induced dipole - induced dipole forces occur in?

A

ALL molecules

214
Q

Which Van der Waal force occurs in ALL molecules?

A

Induced dipole - induces dipole forces

215
Q

What do dipole-dipole forces occur in?

A

Molecules containing a dipole (polar covalent bond)

216
Q

Which Van der Waal force occurs in molecules containing a dipole?

A

Dipole-dipole forces

217
Q

What does a dipole include?

A

One end with a slightly positive charge
Once end with a slightly negative charge
(Due to differences in electronegativities)

218
Q

What’s the name for a molecule with one end that has a slightly positive charge and the other with a slightly negative charge?

A

Dipole

219
Q

Why do dipoles exist?

A

Due to differences in electronegativity

220
Q

Which Van der Waal forces are temporary and which are permanent?

A

Temporary - induced dipole - induced dipole forces
Permanent - dipole dipole forces

221
Q

Dipole-dipole forces

A

When dipoles arrange themselves so that the negative region of one molecule is close to the positive region of another molecule

222
Q

When dipoles arrange themselves so that the negative region of one molecule is close to the positive region of another molecule

A

Dipole-dipole forces

223
Q

Which type of force is generally referred to with “Van der Waal force”?

A

Induced dipole -induced dipole force

224
Q

Which Van der Waal force strengthens intermolecular forces doing between molecules the most?

A

Dipole-dipole force

225
Q

What do dipole-dipole forces do more than induced dipole - induced dipole forces?

A

Strengthen intermolecular forces

226
Q

Compounds with which type of forces have the highest boiling points with similar molar mass - dipole dipole or induced dipole-induced dipole?

A

Dipole-dipole forces

227
Q

How does having stronger intermolecular forces affect molecules with dipole-dipole forces? (Physical property)

A

Higher boiling point

228
Q

What are two molecules with identical molar mass that have completely different boiling points and why?

A

Propanone and butane
Much higher in propanone - dipole dipole forces
Induced dipole - induced dipole in butane

229
Q

What’s propanone also known as?

A

Acetone

230
Q

What’s acetone?

A

Propanone

231
Q

What’s the issue with dipole-dipole forces?

A

Dipoles aren’t always aligned to produce an attraction between them due to the random movements of molecules
Very weak

232
Q

Which type of force has an issue with the alignment of dipoles?

A

Dipole dipole forces

233
Q

How do dipole dipole forces get stronger?

A

Strength of the force increases with the number of electrons in the molecule (i.e - its size)

234
Q

What does a larger molecule mean for the dipole-dipole force?

A

More electrons in the molecule - strength of the force increases

235
Q

What’s hydrogen bonding a special case of?

A

The dipole-dipole force

236
Q

Name a special case of a dipole-dipole force?

A

Hydrogen bonding

237
Q

Describe the trend in terms of boiling points for the period II hydrides compares to period III and explain why this is unexpected

A

Boiling points of period II hydrides are greater than period III
You’d expect the intermolecular forces to be stronger in period III

238
Q

What’s proof for the existence of hydrogen bonding?

A

The fact that the boiling points of period II hydrides are reader than period III (which is unexpected as you’d expect the intermolecular forces to be stronger in period III) - must be a stronger intermolecular force

239
Q

Hydrogen bond

A

An electrostatic force of attraction which forms between a hydrogen atom bonded to a highly electronegative atom in one molecule and a highly electronegative atom such as N, O or F in another molecule

240
Q

An electrostatic force of attraction which forms between a hydrogen atom bonded to a highly electronegative atom in one molecule and a highly electronegative atom such as N, O or F in another molecule

A

Hydrogen bond

241
Q

Highly electronegative elements

A

N, O or F

242
Q

Draw and label hydrogen bonding in water

A

(Check notes)

243
Q

Describe the covalent bonds in water

A

Very polar

244
Q

What’s longest - hydrogen bonds or covalent bonds?

A

Hydrogen bonds

245
Q

What does hydrogen bonding occur between?

A

2 electrostatic atoms

246
Q

Why does hydrogen bonding exist?

A

Hydrogen atoms are very small, and the atom in another molecule is highly electronegative

247
Q

Describe the hydrogen atom that attracts a lone pair of electrons for hydrogen bonding

A

Highly polarising 𝛿+ small hydrogen atoms

248
Q

What does the 𝛿+ hydrogen atom attract in a hydrogen bond?

A

A lone pair of electrons form a highly electron ache you’ve atom in another molecule

249
Q

Which bonds are we breaking when boiling water or melting ice?

A

Hydrogen bonds

250
Q

How do we break hydrogen bonds in water

A

Boil water
Melt ice

251
Q

What, apart from water, does hydrogen bonding occur in?

A

Alcohol, ethanol and ammonia

252
Q

What type of bonding occurs in alcohol, ethanol and ammonia?

A

Hydrogen bonding

253
Q

Draw and label hydrogen bonding in ammonia

A

(Check notes)

254
Q

Which physical properties of compounds does hydrogen bonding affect ?

A

-higher boiling points than compounds with similar molar mass and no hydrogen bonding
-more soluble in water

255
Q

What do compounds have higher boiling points than with hydrogen bonding?

A

Compounds with similar molar mass and no hydrogen bonding

256
Q

What type of bonding makes a substance more soluble and gives it a higher boiling point?

A

Hydrogen bonding

257
Q

Compare ice’s density to water

A

Less dense than water (only substance where the solid is less dense than the liquid)

258
Q

Describe the structure of ice

A

Open stucture
Held by hydrogen bonds
Tetrahedral
Angles of 109.5 degrees

259
Q

Why is ice less dense than liquid water?

A

When it melts, hydrogen bonds are broken and water molecules are able to move closer together

260
Q

What properties does hydrogen bonding give liquid water?

A

Unusually high boiling point
High surface tension value

261
Q

What gives water an unusually high boiling point and a high surface tension value?

A

Hydrogen bonding

262
Q

Name 3 types of compounds that are soluble in water

A

Alcohols, carboxylic acids, amines

263
Q

Why are alcohols, carboxylic acids and amines all soluble in water?

A

They form hydrogen bonds with it

264
Q

Is ammonia soluble in water? Why?

A

Yes, because it can for hydrogen bonds with it

265
Q

What type of compounds are soluble in water?

A

Ones that can form hydrogen bond with it

266
Q

What does a compound’s ability to form hydrogen bonds with water do to it?

A

Makes it soluble in water

267
Q

Is methane soluble in water? Why?

A

No, as it only has Van der Waal forces between molecules and cannot form hydrogen bonds with water

268
Q

Give an example of an Intramolecular force

A

Covalent bond

269
Q

What type of force is a covalent bond?

A

Intramoleular

270
Q

Intramolecular forces

A

Within molecules

271
Q

Forces within molecules

A

Intramolecular forces

272
Q

What do Intramolecular forces influence?

A

Chemical properties of molecules

273
Q

What affect ehe chemical properties of molecules?

A

Intramolecular forces

274
Q

Give examples of intermolecular forces

A

Van der Waal’s forces, Hydrogen bonding

275
Q

What type of forces are Van der Waal’s forces and hydrogen bonding types of?

A

Intermolecular forces

276
Q

Where do intermolecular forces exist?

A

Between molecules

277
Q

What type of forces exist between molecules?

A

Intermolecular forces

278
Q

What do intermolecular forces affect (give examples)?

A

The physical properties of molecules (melting and boiling points, solubility)

279
Q

What affects the physical properties of molecules (melting and boiling points, solubility)?

A

Intermolecular forces

280
Q

How do boiling points change down the group and why?

A

Increase down the group due to larger molecules having stronger Van der Waal forces

281
Q

When a compound boils, which bonds are broken and which are not?

A

Covalent bonds are NOT broken
Intermolecular forces ARE broken

282
Q

What’s an example of intermolecular forces being broken when a compound boils, not covalent bonds?

A

When water boils into steam, it doesn’t turn into hydrogen and oxygen. Steam is gaseous water.

283
Q

List the three main forces in order of strength, starting from the strongest

A

Covalent bonds
Hydrogen bonds
Van der Waal’s forces

284
Q

Which force us the strongest?

A

Covalent bonds

285
Q

Which force is the weakest?

A

Van der Waal’s forces

286
Q

Why are covalent bonds stronger than hydrogen and Van der Waal’s forces?

A

Distance between atoms is shorter due to increased attraction

287
Q

Draw ethanol (C2H2OH) forming hydrogen bonds with water

A

(Check notes)

288
Q

What would make something more insoluble in water? Why?

A

More non-polar groups, due a decreased effect of hydrogen bonds

289
Q

What would more non-polar groups do to a compound in water?

A

Make it more insoluble due to a decreased effect of hydrogen bonds

290
Q

What would decrease the effect of hydrogen bonds? What would this lead to?

A

More non-polar groups - become more insoluble in water

291
Q

What do we use to determine shapes of molecules and ions?

A

Valence shell electron pair repulsion theory (VSEPR)

292
Q

VSEPR

A

Valence shell electron pair repulsion theory

293
Q

What is the general rule of VSEPR?

A

The shape adopted by a simple molecule or ion is that which keeps repulsive forces to a minimum

294
Q

What’s VSEPR used for?

A

Determining the shapes of molecules or ions

295
Q

How is VSEPR used to determine the shapes of molecules or ions?

A

By defending the number of electron pairs in the outer shell (valence shell) of a central atom

296
Q

Outer shell

A

Valence shell

297
Q

Valence shell

A

Outer shell

298
Q

The outer shell of which atom do we use for VSEPR?

A

A CENTRAL atom

299
Q

What do we determine for a central atom in VSEPR?

A

The number of electron pairs in the outer shell

300
Q

What does the shape of a simple molecule or ion do?

A

Keep repulsive forces to a minimum

301
Q

What type of bonds do molecules have?

A

Covalent bonds

302
Q

What do covalent bonds consist of and what’s significant about these?

A

A pair of electrons
Electrons are negatively charged
Each bond repels other bonds

303
Q

Why do bonds repel other bonds?

A

Electrons are negatively charged (a covalent bond consists of a pair of electrons)- each bond repels other bonds

304
Q

What type of bond consists of a pair of electrons?

A

Covalent bond

305
Q

What do bonds duo due to them being repulsive of each other?

A

Push each other as far apart as possible to reduce repulsive forces

306
Q

Why do bonds push each other as far apart as possible?

A

To reduce repulsive forces

307
Q

What would equal repulsions of bonds cause?

A

Equally spaced bonds

308
Q

What causes equal spaces between bonds?

A

Equal repulsions

309
Q

What would bonds be with less repulsive forces?

A

Further

310
Q

When would bonds be further away from each other?

A

With less repulsive forces

311
Q

How would bonds be with greater repulsive forces?

A

Closer

312
Q

When would bonds be closer?

A

With greater repulsive forces

313
Q

What’s a simple molecule?

A

One with a central atom and other’s bonded to it

314
Q

Molecule with a central atom and others bonded to it

A

Simple molecule

315
Q

What do most simple molecules have?

A

Standard shapes
Equal bond angles

316
Q

Why do most simple molecules have standard shapes and equal bond angles?

A

Equal repulsions between bond pairs

317
Q

What do equal repulsion’s between bond pairs in simple molecules do?

A

Give them standard shapes and equal bond angles

318
Q

What affects the angles between bonds and therefore the shapes of molecules?

A

Lone pairs on the central atom

319
Q

Where do lone pairs cause an effect?

A

On the central atom of a molecule

320
Q

What do lone pairs on the central atom of a molecule affect?

A

-angles between bonds
-shapes

321
Q

Bond pairs

A

These electrons are spread out so that they spend time around both atoms in the bond

322
Q

These electrons are spread out so that they spend time around both atoms in the bond

A

Bond pairs

323
Q

Lone pairs

A

They’re attached to 1 atom only and are not involved in bonding

324
Q

They’re attached to 1 atom only and are not involved in bonding

A

Lone pairs

325
Q

Do bond pairs or lone pairs have a greater power of repulsion? Why?

A

Lone pairs as they occupy a smaller volume of space

326
Q

Which type of pairs of electrons occupy the smallest volume of space and what does this mean?

A

Lone pairs, so they have a greater power of repulsion

327
Q

How are electrons found in the outer shell around central atoms?

A

In pairs

328
Q

Where are electrons found in pairs?

A

Around central atoms

329
Q

What do electron pairs do to each other?

A

Repel one another as far away as possible until they’re at their most stable spatial arrangement

330
Q

What leads to a stable spartial arrangement in a molecule?

A

Electron shells repelling one another as far away as possible

331
Q

What repel each other as far away as possible for a stable spartial arrangement in a molecule?

A

Electron pairs

332
Q

Sequence of repulsion

A

Least repulsive: bond pair-bond pair
Lone pair-bond pair
Most repulsive: Lone pair-lone pair

333
Q

Which pairs of electrons are most repulsive of each other?

A

Lone pair-lone pair

334
Q

Which pairs of electrons are least repulsive of each other?

A

Bond pair-bond pair

335
Q

When do we confide the affects of lone pairs?

A

After the arrangement of electron pairs has been worked out

336
Q

2 electron pairs…
Shape?
Bond angle?
Example?

A

Linear
180°
BeCl2

337
Q

How many electron pairs does a linear shaped molecule have?

A

2

338
Q

2 WHAT does a linear arrangement of a molecule have?

A

Electron pairs

339
Q

3 electron pairs…
Shape?
Bond angle?
Example?

A

Trigonal planar
120 °
BF3

340
Q

4 electron pairs…
Shape?
Bond angle?
Example?

A

Tetrahedral
109.5 °
CH4

341
Q

5 electron pairs…
Shape?
Bond angle?
Example?

A

Trigonal bipyramid
90/120 °
PCl5

342
Q

6 electron pairs…
Shape?
Bond angle?
Example?

A

Octahedral
90 °
SF6

343
Q

Bond angle 180 ° shape and electron pairs

A

Linear, 2

344
Q

Bond angle 120 ° shape and electron pairs

A

Trigonal planar, 3

345
Q

Bond angle 109.5 ° shape and electron pairs

A

Tetrahedral

346
Q

Bond angle 90 °/120 ° shape and electron pairs

A

Trigonal bipyramid, 5

347
Q

Bond angle 90 ° shape and electron pairs

A

Octahedral, 6

348
Q

What do bond angles represent in molecules?

A

The furthest distance bonding pairs can get

349
Q

Around which pair do lone pairs start causing effects to the shape and bond angle of a molecule?

A

Around the central atom

350
Q

What around the central atom causes effects for the bond angle and shape of molecules?

A

Lone pairs

351
Q

What would we expect to form with BeCl2 and why is this not the case?

A

Ionic bonds, but Be is small with a high charge, and so has a high polarising power to form covalent compounds

352
Q

Why does BeCl2 not form ionic bonds?

A

Be is small with a high charge, so it has a high polarising power to form covalent compounds

353
Q

Beryllium dichloride shape + explanation

A

(See notes)

354
Q

Boron trifluoride shape and explanation

A

(See notes)

355
Q

What type of diagram do we have to draw to represent the 3D shape of molecules?

A

Wedge diagrams

356
Q

Methane shape + explanation

A

(See notes)

357
Q

Phosphorus (V) chloride shape + explanation

A

(See notes)

358
Q

What can phosphorus do?

A

Make use of its d orbitals to expand its octet

359
Q

Name 2 elements that can make use of their d orbitals to expand their octets

A

Phosphorus, sulphur

360
Q

How do phosphorus and sulphur expand their octets?

A

Make use of their d orbitals

361
Q

What do potassium and sodium make use of their d-orbitals for?

A

Expanding their octets

362
Q

Sulphur (VII) shape + explanation

A

(See notes)

363
Q

Sketch a linear shape molecule

A

(Check notes)

364
Q

Sketch a Trigonal planar shaped molecule

A

(See notes)

365
Q

Sketch a tetrahedral shaped molecule

A

(See notes)

366
Q

Sketch a Trigonal bipyramid molecule

A

(See notes)

367
Q

Sketch an octahedral molecule

A

(See notes)

368
Q

How do we work out the shapes of molecules and ions?

A

1.number of electrons in the outer shell of the central atom
2.number of electrons provided by the other atoms (1 per atom)
3. (For ions) - what is the contribution of charge?
Add 1 electron for every negative charge
Remove 1 electron for every positive charge
4.number of electron pairs (divide total by 2)
5.number of bond pairs (formula shows) and lone pairs (whatever’s left over) - what effect does this have on the shape?

369
Q

How many electrons does each attached atom provide?

A

1

370
Q

What are irregular shapes caused by?

A

Extra repulsion caused by lone electrons

371
Q

What does extra repulsion from lone electrons cause?

A

Irregular shapes

372
Q

Name 2 molecules with irregular shapes - why?

A

Ammonia and water due to the greater repulsive effect of the lone pair reducing the bond angle

373
Q

Is the bond angle larger or smaller than expected with lone pairs causing their repulsive effects?

A

Smaller

374
Q

Draw (approx.) ammonias shape + explain

A

(See notes)

375
Q

Draw waters (approx.) shape and explain

A

(See notes)

376
Q

What shape does ammonia have?

A

Based on a tetrahedron, but as one of the pairs is a lone pair, it has a more pyramidal shape

377
Q

Molecule with a pyramidal shape

A

Ammonia

378
Q

Molecule with an angular shape

A

Water

379
Q

What shape is a water molecule?

A

Based on a tetrahedron, but has an angular shape due to lone pairs

380
Q

Sketch CO2s molecule + explain

A

(See notes)

381
Q

How do we calculate the shape of a molecule itch double bonds and why?

A

It’s calculated in the same way, as the double bond repels other bonds as if it were single, causing the same shape

382
Q

Difference between the shape of molecules with double bonds and regular ones

A

No difference - the bond repels other bonds as if it were single

383
Q

What’s important to remember when sketching CO2’s molecule?

A

It has double bonds

384
Q

What do we need to remember to include when drawing hydrogen bonds?

A

-polarisation (little charges) of everything involved
-lone electrons
-correctly placed hydrogen bonds

385
Q

What makes a bond polar?

A

The elements involved having a difference in electronegativity

386
Q

What does a difference in electronegativity mean in a bond?

A

That it’s polar

387
Q

Give 2 examples of species containing a coordinate bond

A

Ammonium ion (NH4+)
Hydrated proton (H30+)

388
Q

What do we do when asked to show any permanent dipoles?

A

Draw the little charges

389
Q

How is ammonia able to act as a base?

A

Has a lone pair of electrons on the nitrogen atom, so it can form a coordinate bond
So, it accepts a proton H+

390
Q

What’s the strongest from the following?
dipole-dipole
induced dipole-induced dipole

A

dipole-dipole

391
Q

What are induced dipole-induced dipole forces usually found in?

A

diatomics

392
Q

What does increased electronegativity mean in terms of the time taken for a reaction to take place?

A

More electronegative = faster reaction

393
Q

Shape of molecule with 3 bond pairs and 1 lone pair

A

Trigonal pyramidal

394
Q

Shape of molecule with 2 bonding pairs and 2 lone pairs

A

Bent

395
Q

Do noble gases have high or low boiling temperatures? Why?

A

Low
Does not form molecules and exists as separate atoms
Atoms are held together by weak induced dipole- induced dipole forces

396
Q

What do I need to remember to put down in all VSEPR questions?

A

That the shape is laid out in this way in order to keep repulsive forces to a minimum

397
Q

Name of shape of molecule with 3 bond pairs and 1 lone pair

A

Pyramidal

A level Chemistry (39 decks)

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