1 Structure and bonding

Question 1

What is the charge of the ions in each group?

Answer 1

1. +1
2. +2
3. +3
4. left out
5. -3
6. -2
7. -1
8. left out

Question 2

Why do groups 4 and 0 not follow the pattern of charges of ions?

Answer 2

Group 0 already has a full outer electronic shell so will not need to form an ion which has lost or gained electrons
Group 4 only has 4 electrons on its outer shell but its half stable so it won’t take or give electrons to become a charged ion

Question 3

Why do ionic compounds have high melting and boiling points?

Answer 3

Because they form a lattice with opposite charged ions attracting each other very strongly which means it requires more energy to break apart the bonds

Question 4

What are the conditions of the charge for ionic compounds?

Answer 4

They must balance out to be a neutral charge- 0

They cancel each other out

Question 5

What is ionic bonding a bond between?

Answer 5

A metal and a non metal

Question 6

What is a compound?

Answer 6

A substance containing 2 or more elements which are chemically combined

Question 7

How do atoms achieve a stable arrangement in covalent bonding?

Answer 7

By sharing electrons

Question 8

How do atoms achieve a stable arrangement in ionic bonding?

Answer 8

By transferring electrons

Question 9

What is the very strong force of attraction called in ionic bonding?

Answer 9

The electrostatic force of attraction

Question 10

What do we call the structure of an arrangement of ions in ionic bonding?

Answer 10

A giant structure (lattice)

Question 11

What does the formula of an ionic compound show?

Answer 11

The ratio of ion present in the compound

Question 12

How are the atoms in molecules held together in covalent bonding?

Answer 12

By shared pairs of electrons which are called strong bonds between the atom’s covalent bonds

Question 13

Name two examples of giant covalent structures…

Answer 13

Diamond: each carbon atom forms four covalent bonds with its neighbours forming a rigid lattice
Silica/ silican dioxide

Question 14

What are the general properties of giant covalent structures?

Answer 14

• the bonds are very strong
• the bonds have a regular geometry
• the atoms form a very strong lattice

Question 15

Nitrogen and carbon dioxide are very nonreactive… what does this tell us about covalent bonds?

Answer 15

The bonds are strong and stable
Intramolecular bonds
Not interested in other reactions

Question 16

Why are most covalent bonded compounds gases?

Answer 16

The intramolecular bonds are strong and stable

Question 17

What are the structures of metals like?

Answer 17

Metals have giant structures made up of metal atoms which are closely packed together and arranged in regular patterns of layers
This means they can form crystals

Question 18

When are you likely to be able to see crystals on the surface of metals?

Answer 18

• surface of aluminium foil

- on iron objects which are galvanised to protect from rusting (zinc coated)

Question 19

How does metallic bonding work?

Answer 19

• Metal ions are held together by electrons from the outermost shell (highest energy level) of the metal atoms
• The positive ions that this produces (and the sea of ‘free’ electrons) are held together by strong electrostatic forces which bond the metal ions like glue
• The electrons in metals are free to move around throughout the structure

Question 20

What are the outermost electrons in a metal atom termed as and what do they do?

Answer 20

They are described as a sea of DELOCALISED electrons which rapidly move binding the ions together

Question 21

True or false? ‘The more electrons there are in its outer shell, the stronger the metal structure’

Answer 21

True

Question 22

How do metals conduct electricity?

Answer 22

The free delocalised electrons are able to attract to the ions so they can conduct the electricity and transfer the charge to other ions quickly

Question 23

How do metals conduct heat?

Answer 23

Free, delocalised electrons absorb electricity and gain energy, turning into kinetic energy as they move and vibrate- this means they hit each other and more energy is passed between them, generating heat

Question 24

Why do metals have high melting and boiling points?

Answer 24

The bonds have to break to metallically bond, therefore a lot of energy is used to do this- this means that there are high melting and boiling points because of the energy needed to turn it into a liquid/gas- their electrons are strong