Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

RGS 4th Form Chemistry > 2 Covalent Bonding > Flashcards

2 Covalent Bonding Flashcards

1
Q

Why do giant covalent compounds have high melting points?

A
  • many strong covalent bonds
  • in giant lattice structure
  • require a lot of energy to overcome
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What state of matter is chlorine, bromine and iodine at room temperature?

A

Chlorine- gas

Bromine- liquid

Iodine-solid

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

How do you draw the structure of graphite?

A
  • Draw a minimum of three hexagons in each layer
  • Off set the layers and add dotted vertical lines between layers to represent the weak force between layers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What sort of bond is between the carbon and oxygen in carbon dioxide?

A

Double covalent bond

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

If chlorine water is added to sodium iodide solution, the solution turns from colourless to brown.

Why does this happen?

A

Chlorine water (colourless) is more reactive than iodide

Cl2+ 2NaI –> 2NaCl + I2

colourless brown

Chlorine displaces the iodide ion to form iodine

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

Describe the forces on any outer shell electrons

A

Force of attraction between outer electrons (-) and (+) positive nucleus

Force of repulsion between outer electrons (-) and electrons (-) in middle shells (called electron shielding)

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

What is the dot cross diagram for chlorine?

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

Describe the appearance of the element chlorine

A

pale green gas at room temperature

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

What are the names of the two types of covalently bonded substances?

A

Simple covalent e.g. water

Giant covalent e.g. diamond

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

Below are the many possible structure of the element sulfur.

What are these structures called, which are different structural forms of the same element?

A

allotropes

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

How do you draw the structure of diamond?

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

What is the dot cross diagram for oxygen?

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

Iodine is a larger atom than bromine.

This means the outer shell is further from nucleus and there is a weaker force of attraction on electrons

This also means there is more electron shielding, more repulsion on the outer shell electrons

What affect does this have on iodine’s reactivity compared to bromine?

A

Iodine is less reactive than bromine.

Remember group 7 wants to gain or share 1 electron and i_odine has less of a pull from the nucleus_ and more repulsion from electrons in the middles shells.

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

Describe the appearance of chlorine, bromine and iodine

A

Chlorine- pale green gas

Bromine- red liquid

Iodine- grey solid

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

What would you observe if you add colourless chlorine water to potassium iodide

KI + Cl2

A

It would turn from colourless to brown

chlorine is more reactive than iodine

chlorine will displace iodide ion

2KI + Cl2 –> KCl + I2

colourless brown

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

Graphite is made of layers which have weak intermolecular forces between them

The layers can easily slide over one another

Does this make graphite hard or soft?

A

soft

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

What would you observe if you add orange bromine water to potassium iodide

KI + Br2

A

It would turn from orange to brown

bromine is more reactive than iodine

bromine will displace iodide ion

2KI + Br2 –> 2KBr + I2

orange brown

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

Diamond is an allotrope of carbon.

Carbon has 4 bonds and forms a tight tetrahedral structure with no layers.

It is entirely made of strong covalent bonds and has no weak intermolecular forces

Will diamond be hard or soft?

A

hard

contains no layers which easily slide over one another.

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

State two uses of diamond and two uses of graphite

A

diamond- cutting tools, jewellery

graphite- lubricant and electrodes for electrolysis

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

Describe the difference in solubility of both ionic and covalently bonded substances in water

A

-Ionic compounds have generally high solubility

(polar solvents like water can easily pull oppositely charged ions from the structure- dissolving it)

-Covalent compounds have generally low solubility

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

What is a allotrope? Give two examples

A

Same element but different structure - or are chemically bonded in a different way

e.g.

diamond and graphite are allotropes

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

What type of atoms covalently bond together?

metal & metal

non-metal & metal

non-metal and non-metal

A

non-metal and non-metal atoms covalently bond

they share electrons.

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

What is the displayed formula for water?

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

Which sort of bond will form between sulfur and oxygen?

A

Both non-metals, so covalent bond

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Draw the dot cross diagram for ammonia
26
Covalent bonds form between which types of atoms? Ionic bonds form between which types of atoms?
**Covalent bonding** happens **between non-metals**- they share electrons **Ionic bonding** happens **between metals and non-metals**- electrons are transferred from the metal to the non-metal
27
Give three examples of simple covalent compounds
1. water H2O 2. methane CH4 3. ammonia NH3 4. chlorine Cl2 5. Carbon dioxide CO2
28
_Chlorine_ is a **green gas** _Bromine_ is a **red liquid** _Iodine_ is a **grey solid** What colours are these halogens when in solution such as in displacement reactions?
_Chlorine_ solution is **colourless** _Bromine_ solution is **orange** _Iodine_ solution is **brown**
29
Hydrogen chloride is a covalently bonded substance. What happens when hydrogen chloride is added to methylbenzene?
* In methylbenzene (which is a non-polar solvent) hydrogen chloride **does not dissociate**, it is not pulled apart. * There are **no H+ ions present** therefore blue litmus paper stay blue. * It is **not acidic**
30
Fluorine is a smaller atom than chlorine. ## Footnote This means the _outer shell is closer to nucleus_ and there is a _greater force of attraction on electrons_ This also means there is l_ess electron shielding_, _less repulsion on the outer shell electrons_ **What affect does this have on fluorine's reactivity?**
Fluorine is more reactive than chlorine. *Remember group 7 wants to gain or share 1 electron!*
31
What would you observe if you add colourless chlorine water to sodium chloride? NaCl + Cl2
Nothing *Solution would stay colourless* chlorine _will not_ displace chloride ion chlorine will not displace itself
32
Describe the reactivity in Group 7- The halogens
Reactivity increases up group 7 Fluorine is the most reactive halogen - lowest number of shells, **outer shell closer to positive nucleus** - **larger attractive forces** between nucleus and outer electrons - **less electron shielding** - less repulsion from electrons - **greater pull on electrons, less energy** required to react**, more reactive**
33
Is the substance below simple covalent or giant covalent?
Simple covalent
34
What is the dot cross diagram for ethene?
Notice the double bond between the two carbon atoms!
35
Describe the appearance of the element chlorine
pale green gas at room temperature
36
Why are simple molecular substances usually gaseous at room temperature?
They have low melting points weak intermolecular forces little energy is needed to overcome them
37
Use the change in appearance of the halogens below to deduce the appearance of astatine (Below iodine in Group 7) Chlorine- pale green gas Bromine- red liquid Iodine- grey/purple solid
Black solid
38
What sort of bond is between the nitrogen atoms in nitrogen?
Triple covalent bond
39
What giant covalent substance is shown in the image below?
diamond
40
What would you observe if you add colourless chlorine water to sodium bromide? KBr + Cl2
It would turn orange chlorine will displace bromide ion chlorine is more reactive than bromine 2KBr + Cl2 --\> 2KCl + Br2
41
What is the dot cross diagram for nitrogen?
Notice the triple bond between the nitrogen!
42
Hydrogen chloride is a covalently bonded substance. What happens when hydrogen chloride is added to water?
* In water (which is a polar solvent) hydrogen chloride **dissociates** (or is pulled apart) into an H+ ion and Cl- ion. * There are **H+ ions present** therefore blue litmus paper would **turn red**. * This is forms **hydrochloric acid**.
43
What sort of bond is between oxygen atoms in oxygen?
Double covalent bond
44
Why is graphite soft?
- It has **weak intermolecular forces between its layers** - layers can **easily slide over each other** - it **does not hold its structure** when deformed
45
What would you observe if you add colourless chlorine water to sodium chloride? NaCl + Cl2
Nothing *Solution would stay colourless* chlorine _will not_ displace chloride ion chlorine will not displace itself
46
What would you observe if you add colourless chlorine water to potassium iodide KI + Cl2
It would turn from colourless _to brown_ chlorine will displace iodide ion chlorine is more reactive than iodine 2KI + Cl2 --\> 2KCl + I2
47
What type of bond is an **electrostatic force of attraction** between a **shared pair of electrons** and the **positively charged nucleus of an atom.**
Covalent bond
48
Describe what happens to the boiling point as you go down Group 7 (The Halogens)
Boiling point increases down the group
49
What is a covalent bond?
The **electrostatic attraction** between a **shared pair of electrons** and the **nucleus** of an atom.
50
What are the similarities and differences between a covalent bond and an ionic bond?
_Same_- both **electrostatic attraction** _Different_- Covalent bond- **non-metals & non-metal** Ionic bond **- metal & non-metal** _Different-_ Covalent bond- between a **shared pair of electrons** and **nucleus** of an atom Ionic bond- between **oppositely charged ions**
51
What would you observe if you add brown iodine water to sodium chloride? NaCl + I2
Nothing *Solution would stay brown* Iodine _will not_ displace chloride ion Iodine is less reactive _than chlorine_
52
What is the dot cross diagram for hydrogen chloride?
53
Name all the diatomic molecules- remember that they are covalently bonded
Hydrogen Nitrogen Fluorine Oxygen Iodine Chlorine Bromine A goof mneumonic is 'Have No Fear Of Ice Cold Beer'
54
Why do simple covalent compounds have low melting points?
- **weak intermolecular forces** - require l**ittle energy to overcome** **- low melting point**
55
Br2 + CuI2 --\> CuBr2 + I2 In the **_halogen displacement_** bromine is **more reactive** than iodine and **displaces it,** what is oxidised and what is reduced?
Br2 + 2e- --\> 2Br- 2I- --\> I2 + 2e- OIL RIG Bromine is reduced- gained electron Iodide ion is oxidised- loses electron
56
Which sort of bond will form between magnesium and oxygen?
One metal and other non-metal. Ionic bond would form.
57
What would you observe if you add colourless chlorine water to sodium bromide? KBr + Cl2
It would turn from _colourless to orange_ chlorine will displace bromide ion chlorine is more reactive than bromine 2KBr + Cl2 --\> 2KCl + Br2
58
Explain why covalent compounds do not conduct electricity
* There are no mobile ions or electrons * No charged particles to carry charge
59
What is similar between a metallic structure, ionic structure and giant covalent structure?
* They all have **many strong bonds** in a **giant structure.** * They all require **a lot of energy to overcome** * They all have **high melting points**
60
What is the dot cross diagram for carbon dioxide?
61
Why do carbon & carbon share electrons when bonded but sodium & chlorine transfer electrons when bonded?
* Two carbon atoms have **equal 'pull'** or 'affinity for electrons. Therefore they **share** electrons. whereas, * Chlorine has a **large**'pull' or **affinity** for electrons and sodium does not. Therefore sodium **transfers one electron** to chlorine.
62
What is the dot cross diagram for water?
63
Is the substance below simple covalent or giant covalent?
Giant covalent
64
Compare and contrast the state of **ionic** and **simple** **covalent** compounds at room temperature
* Ionic compounds are **all solid** * Simple covalent compounds can be **gaseous, liquid or solid** at room temperature
65
Describe the appearance of the element iodine
grey/purple solid at room temperature
66
How are metallic bonds different from/similar to covalent bonds?
Same: both are an electrostatic attraction Different: Metallic- attraction is between **positive metal ions** and a **sea of delocalised electrons** Covalent is between a **nucleus** and a **shared pair of electrons.**
67
What is the dot cross diagram for hydrogen?
68
Which sort of bond would form between copper and copper?
Both metals - metallic bond.
69
What is the dot cross diagram for methane?
70
Why does graphite (a non-metal) conduct electricity?
- Graphite is made of layers of carbon atoms with **three bonds**. - Carbon is in group 4 and has **four outer electrons.** - This one **electron is free to move** (delocalised) within the layers of carbon - and can **carry charge**.
71
What are the similarities and differences between a _covalent bond_ and _metallic bond_?
_Same:_ They are both an **electrostatic attraction** _Difference:_ Covalent bond- is between a **shared pair of electrons** and the **nucleus** of an atom Metallic bond- is between **a metal ion** and a **sea of delocalised electrons** _Difference:_ Covalent bond- between non-metals only Metallic - between metals only
72
Compare and contrast the properties of graphite and diamond **appearance** **harness** **thermal conductivity** **electrical conductivity** **use**
73
What is the dot cross diagram from ammonia?
74
How many outer electrons do the halogen group have?
seven outer electrons All halogens atoms form diatomic simple molecular molecules F2 Cl2 I2
75
What would you observe if you add orange bromine water to sodium chloride? NaCl + Br2
Nothing *Solution would stay orange* Bromine _will not_ displace **chloride ion** Bromine is less reactive _than chlorine_
76
Explain why graphite makes a good lubricant
- Graphite has **weak forces between the layers** - layers can **slide over** one another easily
77
Give three examples of giant covalent compounds
1. graphite 2. diamond 3. silicon dioxide
78
Describe the appearance of the element bromine
red liquid at room temperature
79
Describe the appearance of the element bromine
red liquid at room temperature
80
Fluorine is a smaller atom than chlorine. ## Footnote This means the _outer shell is closer to nucleus_ and there is a _greater force of attraction on electrons_ This also means there is l_ess electron shielding_, _less repulsion on the outer shell electrons_ **What affect does this have on fluorine's reactivity?**
Fluorine is more reactive than chlorine. *Remember group 7 wants to gain or share 1 electron!*
81
How are the covalent bonds between carbon in diamond different from the covalent bonds between carbon in graphite?
Diamond- all four outer shell electrons are used Graphite- only 3 outer shell electrons are used- fourth electron exists between the layers and is delocalised
82
Why does tetrachloromethane have a higher boiling point than trichloromethane?
Tetrachloromethane has a **higher formula mass**, therefore has a **higher boiling point** * - **larger forces** between the molecules* * -**more energy** needed to overcome them*
83
Is fullerene giant covalent or simple covalent?
Simple covalent *It is molecular and has a definite size*

RGS 4th Form Chemistry (5 decks)

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