Chemical Bonding

Question 1

What is ionic bonding?

Answer 1

Ionic bonding involves an attraction between oppositely charged ions.

Question 2

Where are ionic bonds found?

Answer 2

Found in compounds made from metal and non-metals.

Question 3

What is covalent bonding?

Answer 3

Covalent bonding involves 2 atoms sharing one or more pairs of electrons.

Question 4

Where are covalent bonds found?

Answer 4

Found in most non-metal elements and in compounds of non-metals.

Question 5

What is metallic bonding?

Answer 5

Metallic bonding involves an attraction between positively charged ions and negatively charged delocalised electrons.

Question 6

Where are metallic bonds found?

Answer 6

Found in metals and alloys (mixtures of metals and other substances).

Question 7

How many types of chemical bond are there and name these:

Answer 7

3: Covalent, metallic and ionic.

Question 8

Which type of bonding happens in most non-metal elements?

Answer 8

Covalent.

Question 9

What are ions?

Answer 9

Ion are charged particles. They are created when an atom or molecule gains or loses electrons.

Question 10

How are ions created?

Answer 10

Gaining electrons creates a negatively charged ion; losing electrons creates a positively charged ion.

Question 11

How are positive ions created?

Answer 11

Usually created when an atom or molecule loses electrons.

Question 12

What can positive ions also be called?

Answer 12

Cations.

Question 13

The metals in group 1 and 2 can easily lose..

Answer 13

…electrons to become positively charged ions.

Question 14

How are negative ions created?

Answer 14

When an atom or molecule gains electrons.

Question 15

What are negative ions also called?

Answer 15

Anions.

Question 16

The non-metals in group 7 are most likely to…

Answer 16

…gain electrons to fill up their electrons shell and become negatively charged.

Question 17

Ions can be:

Answer 17

Single elements (eg F-) 
A group of element with an overall charge (eg SO42-)

Question 18

How does the nucleus of an atom change when it gains electrons?

Answer 18

It doesn’t.

Question 19

Positive ions are usually made when an atom or molecule…

Answer 19

loses electrons.

Question 20

What happens when atoms form ions?

Answer 20

They try to fill up or empty their outer electron shell.

Question 21

How do group 1 metals form ions?

Answer 21

Always lose 1 electron to form positive ions with a charge of +1.

Question 22

How do group 2 metals form ions?

Answer 22

Always lose 2 electrons to form doubly positive ions.

Question 23

How do non-metals form ions (groups 6 and 7)?

Answer 23

Always gain electrons to form (become) negative ions.

Question 24

How do noble gases (group 0) form ions?

Answer 24

Already have a full outer shell so are unreactive and don’t normally form ionic bonds with other elements.

Question 25

Materials with ionic bonds usually...

Answer 25

Only conduct electricity when molten/dissolved. | Have high melting points.

Question 26

Sodium is in group 1 and oxygen is in group 6. In the dot-and-cross diagram for sodium oxide, how many sodium ions would there be?

Answer 26

2.

Question 27

Through which diagram can we show the transfer of electrons and ions formed?

Answer 27

Dot and cross diagrams.

Question 28

What is an ionic compound?

Answer 28

When millions of metal atoms transfer their outer electrons to millions of non-metal atoms at the same time, resulting in oppositely charged ions held together in ionic lattices.

Question 29

What is an ionic lattice?

Answer 29

Giant structures that are held together by strong electrostatic forces between oppositely charged ions.

Question 30

What are electrostatic forces?

Answer 30

Called ionic bonds that extend in all directions within the lattice.

Question 31

What does an empirical formulae help us to do?

Answer 31

Helps us to work out the proportion of each ion in a compound and is the simplest ratio of ions possible of an ionic compound.

Question 32

What is the empirical formulae of Ca2+ and F- ions?

Answer 32

In order for the charges to balance out and for the overall formula to be neutral, there must be 2 F- ions for each Ca2+ ion. The empirical formula is CaF2.

Question 33

Facts about ionic lattices...

Answer 33

Giant structures. Held together by electrostatic forces. Contain negatively charged non-metal ions. Contain positively charged metal ions.

Question 34

Why are Covalent bonds strong?

Answer 34

Because the shared electrons are attracted to the nucleus of both atoms.

Question 35

Covalently bonded substance can be:

Answer 35

``` Small molecules (water) Large molecules (such as polyester and silk) Giant covalent structures (diamond) ```

Question 36

Describe the structure of an metal:

Answer 36

Giant structures of regularly arranged electrons. A regular lattice of cations in a 'sea' of delocalised electrons.

Question 37

What are delocalised electrons?

Answer 37

Not bound to an atom and are free to move around the lattice.

Question 38

Why does delocalisation happen?

Answer 38

Metal atoms have a smaller amount of electrons in their outer shells.