TRIAL EXAM PREP - STRUCTURE & BONDING

Question 1

Describe what happens to electrons in ionic bonding

Answer 1

They are transferred from one atom to another

Question 2

Explain in terms of electrons what occurs when lithium reacts with oxygen to form lithium oxide

Answer 2

Two lithium atoms transfer one electron each to one atom of oxygen
The ions have full outer shells
The ions are then attracted to each other by the electrostatic force of attraction

Question 3

Explain why alloys can be harder than pure metals

Answer 3

They have atoms of different sizes
Which distorts the layers of the structure
And prevent them from sliding over each other easily

Question 4

Explain why using nano particles can often be more cost effective than using larger particles

Answer 4

Fewer particles can be used to achieve the same effect

Question 5

An element is in Group 1. If it forms an ion state what charge it will have

Answer 5

1+

Question 6

Explain why simple molecular substances have low melting points

Answer 6

Weak IMF require little energy to overcome

Question 7

When a substance consisting of small molecules is melted or boiled, identify the forces that are overcome

Answer 7

IMF

Question 8

Explain why Diamond is hard

Answer 8

It has a giant covalent structure
It has strong covalent bonds between atoms
Which are hard to break

Question 9

Give 3 examples of substances with a giant covalent structure

Answer 9

Diamond, silicon dioxide and graphite

Question 10

How many bonds does each carbon atom have in diamond?

Answer 10

4

Question 11

Name 3 properties of diamond

Answer 11

High melting and boiling points
Doesn’t conduct electricity
Very hard

Question 12

Explain how graphite conducts electricity making full reference to its structure and bonding

Answer 12

Each carbon atom has 3 bonds only
There is therefore one delocalised electron per carbon atom
The delocalised electrons are free to carry charge throughout graphite

Question 13

Give a possible risk of using nanoparticles

Answer 13

Escape into the environment with unpredictable effects

Question 14

Give 3 uses of nanoparticles

Answer 14

Catalysts, electronics and medicine

Question 15

Explain why larger molecules have higher melting and boiling points than smaller ones

Answer 15

They have stronger IMF
which require more energy to overcome

Question 16

Describe motions in solids

Question 17

Describe the structure of nanotubes

Answer 17

Hexagonal rings of carbon atoms
Arranged in a hollow cylinder

Question 18

Explain why pure metals have high melting and boiling points

Answer 18

Strong metallic bonds between metal ions and delocalised electrons
Require a lot of energy to overcome

Question 19

Define polymer

Answer 19

A very large molecule consisting of smaller molecules joined together

Question 20

Give 2 properties of ionic substances

Answer 20

High melting and boiling points
Only conduct electricity when molten or in solution

Question 21

Name the type of structure that is made of billions of atoms covalently bonded together

Answer 21

Giant covalent structure

Question 22

An element is in Group 7. If it forms an ion, state what charge it will have

Answer 22

1-

Question 23

Explain why polymers have high melting points relative to substances made of small molecules

Answer 23

They are much larger molecules
So stronger IMF
which require more energy to overcome

Question 24

Describe the structure of a giant ionic lattice

Answer 24

A 3D Network of alternating positive and negative ions held together by the strong electrostatic force of attraction

Question 25

Explain in terms of electrons what occurs when magnesium reacts with chlorine to form magnesium chloride

Answer 25

One magnesium atom transfers one electron to one chlorine atom, and another electron to a second chlorine atom The ions have full outer shells The ions are then attracted to each other by the electrostatic force of attraction

Question 26

Explain why ionic substance conduct electricity in solution

Answer 26

Because the ions are free to move and carry charge throughout

Question 27

..

Question 28

Describe the structure of graphene

Answer 28

One layer of graphite

Question 29

Give a reason for alloying a metal

Answer 29

To make it harder

Question 30

Describe the relationship between the side length of a cube and its SA to volume ratio

Answer 30

As the side length decreases by a factor of 10, the SA to volume ratio increases by a factor of 10

Question 31

Explain why diamond does not conduct electricity

Answer 31

The atoms do not have an overall charge It does not have delocalised electrons So charge cannot flow

Question 32

Name the type of structure that is formed when metals and non metals n react together

Answer 32

Giant ionic structure

Question 33

Explain in terms of electrons what occurs when magnesium reacts with oxygen to form magnesium oxide

Answer 33

Two electrons are transferred from a magnesium atom to an oxygen atom The ions have full outer shells The ions are then attracted to each other by the strong electrostatic force of attraction

Question 34

What are coarse particles often referred to as?

Answer 34

Dust

Question 35

Name the three main types of substance formed from covalently bonded atoms

Answer 35

Small molecules, very large molecules and giant covalent structures

Question 36

Describe the structure of metals

Answer 36

Giant structure Metal ions in layers Delocalised electrons

Question 37

Explain why graphite can act as a lubricant