Structure and Bonding

Question 1

What charge do electrons have?

Answer 1

-1

Question 2

What charge will an ion of lithium take?

Answer 2

1+ (one electron in the outer shell, needs to lose it)

Question 3

What charge will an ion of beryllium take?

Answer 3

2+ (two electrons in the outer shell, needs to lose them both)

Question 4

What charge will an ion of barium take?

Answer 4

2+ (group 2 so two electrons in the outer shell, needs to lose them both)

Question 5

What charge will an ion of fluorine take?

Answer 5

1- (7 electrons in the outer shell, needs to gain one)

Question 6

If something has gained electrons, what charge will it have?

Answer 6

Negative

Question 7

If something has lost electrons, what charge will it have?

Answer 7

Positive (because they have lost a negative!)

Question 8

What charge will an ion of oxygen take?

Answer 8

2- (6 electrons in outer shell so needs to gain two)

Question 9

What charge will an ion of Selenium take?

Answer 9

2- (group 6, so has 6 electrons in the outer shell and needs to gain two)

Question 10

Explain in terms of electrons what occurs when lithium bonds with chlorine

Answer 10

One electron transferred from lithium to chlorine

Question 11

Why do atoms transfer electrons in ionic bonding?

Answer 11

So that they can have full outer shells

Question 12

Explain in terms of electrons what occurs when lithium bonds with fluorine

Answer 12

One electron transferred from lithium to fluorine

Question 13

Explain in terms of electrons what occurs when magnesium bonds with oxygen

Answer 13

Two electrons transferred from magnesium to oxygen

Question 14

Explain in terms of electrons what occurs when beryllium bonds with oxygen (3 marks)

Answer 14

Two electrons transferred from beryllium to oxygen

Question 15

Explain in terms of electrons what occurs when magnesium bonds with chlorine

Answer 15

One electron transferred from magnesium to two different chlorine atoms

Question 16

Explain in terms of electrons what occurs when sodium bonds with oxygen

Answer 16

Two electrons transferred to an oxygen atom from two different sodium atoms

Question 17

Why do sodium ions and chlorine ions form an ionic bond?

Answer 17

There is an electrostatic force of attraction between oppositely charged ions

Question 18

Why don’t sulphur ions and oxygen ions form ionic bonds with each other?

Answer 18

Both have negative charges so would repel

Question 19

What is the name for a substance made of billions of oppositely charged ions joined together?

Answer 19

Giant ionic lattice

Question 20

Define giant ionic lattice

Answer 20

A huge 3D network of ions

Question 21

State the melting points of ionic substances

Answer 21

High

Question 22

Explain why ionic substances have high melting points.

Answer 22

Strong bonds between oppositely charged ions are hard to break

Question 23

Will NaCl(s) conduct electricity?

Answer 23

No

Question 24

Will NaCl (aq) conduct electricity?

Answer 24

Yes (aq stands for aqueous which means it is dissolved in water)

Question 25

Will NaCl (l) conduct electricity?

Answer 25

Yes

Question 26

What does molten mean?

Answer 26

Melted

Question 27

Explain why ionic compounds do not conduct electricity when solid

Answer 27

Because the ions are not free to move

Question 28

Explain why ionic compounds conduct electricity in solution

Answer 28

Because the ions are free to move

Question 29

Explain why ionic compounds conduct electricity when molten

Answer 29

Because the ions are free to move

Question 30

What does soluble mean?

Answer 30

Dissolves in water

Question 31

What does insoluble mean?

Answer 31

Does not dissolve in water

Question 32

Magnesium carbonate is insoluble. What do you need to do before it will conduct electricity?

Answer 32

Melt it

Question 33

Sodium fluoride is soluble. Explain what the easiest way for it to conduct electricity is

Answer 33

Dissolve it in water because this does not require high temperatures

Question 34

Explain why chlorine and fluorine form covalent bonds

Answer 34

They are both non-metals

Question 35

Complete the sentence: In covalent bonds, electrons are _______________________

Answer 35

Shared

Question 36

In ionic bonds, electrons are ___________________

Answer 36

Transferred

Question 37

What is the name given to the structure of diamond, graphite and silicon dioxide?

Answer 37

Giant covalent

Question 38

How many bonds does each carbon have in diamond?

Answer 38

4

Question 39

Explain why diamond has a high melting point

Answer 39

Giant structure, Strong covalent bonds between the atoms, requires a lot of energy to break

Question 40

Explain why most giant covalent substances do not conduct electricity (3 marks)

Answer 40

There are no electrons/ions/charged particles that are free to move

Question 41

Explain why graphite conducts electricity

Answer 41

Has delocalised electrons between the layers that can move through the graphite

Question 42

Explain why graphite can act as a lubricant

Answer 42

Weak forces between layers which are free to slide over each other

Question 43

What is graphene?

Answer 43

One layer of graphite

Question 44

What is a fullerene?

Answer 44

Substance made of carbon atoms arranged in a cage

Question 45

What type of substance are methane and water?

Answer 45

Simple molecular (or simple molecules)

Question 46

What is a molecule?

Answer 46

A group of atoms chemically bonded together

Question 47

Describe the structure of simple covalent molecules

Answer 47

Strong covalent bonds between atoms, weak forces holding the molecules together

Question 48

What are intermolecular forces?

Answer 48

Weak forces between molecules which hold them together

Question 49

Explain why methane has a low melting point

Answer 49

It is a simple molecular substance with weak forces between the molecules (which are easy to break)

Question 50

What is a polymer?

Answer 50

Millions of small molecules joined together in a chain to form a large molecule

Question 51

Describe the main features of metals in terms of their structure

Answer 51

Positive metal ions arranged in layers with delocalised electrons

Question 52

Explain why metals can conduct electricity

Answer 52

Delocalised electrons are free to carry charge

Question 53

Explain why pure metals are soft

Answer 53

Layers of metal ions are free to slide over each other

Question 54

What is an alloy?

Answer 54

A mixture of two or more elements, at least one of which is a metal

Question 55

Give a reason for alloying a metal

Answer 55

To make it harder, to make it less reactive

Question 56

Explain why alloys can be harder than pure metals

Answer 56

Different size of atoms disturb the layers to stop them sliding over each other