Bonding, Structure And The Properties Of Matter

Question 1

What is ionic bonding

Answer 1

• When a metal reacts with a non metal
• the outer electrons are transferred from a metal atom to the non metal atom
• ionic bonding produces ions which have the electronic structure of a noble gas

Question 2

What happens to groups during ionic bonding

Answer 2

• group 1 metals lose 1 electron forming a 1+ ion
• group 2 metals lose 2 electrons forming a 2+ ion
• group 6 non metals gain 2 electrons forming a 2- ion
• group 7 non metals gain 1 electron forming a 1- ion

Question 3

Describe what is happening in the reaction when

Na* + CI*** —> [ Na]+ + [CI**]-

Answer 3

• sodium loses one electron to become a positively charged ion
• chlorine gains this electron to form a negatively charged ion
• opposite charges attract and a strong ionic bond is formed
• both atoms achieve a full outer-energy level

Question 4

What do you do in dot and cross diagrams

Answer 4

Only show the outer levels (only electrons are showed)

Question 5

What is involved in covalent bonding

Answer 5

Only the outer energy levels

Question 6

What is covalent bonding

Answer 6

• Takes place between non metal elements

- a covalent bond is a shared pair of electrons

Question 7

How does a stick diagram look like for H2O

Answer 7

O
/ \
H H

Question 8

What is a double covalent bond

Answer 8

Two shared pairs of electrons (a single covalent bond would be one shared pair of electrons)

Question 9

What does a double covalent bond stick diagram look like

Answer 9

O = O (two lines)

Question 10

What do non metals and metals do when they react together

Answer 10

Form a giant ionic lattice which have strong electrostatic forces (3 dimensional)

Question 11

What does metallic bonding consist of

Answer 11

Positive ions and delocalised electrons

Question 12

What are examples of giant covalent structures

Answer 12

• diamond
• graphite
• graphene
• silicon dioxide

Question 13

What is an ionic bond

Answer 13

A strong electrostatic attraction between positive and negative ions

Question 14

What happens in metallic bonding

Answer 14

Metals lose electrons to form positive ions and delocalised electrons

Question 15

What is a metallic bond

Answer 15

A strong electrostatic attraction between positive metal ions and negative delocalised electrons

Question 16

What are the electrons in a metal

Answer 16

Delocalised

Question 17

Why do metals have high melting and boiling points

Answer 17

• because a great deal of energy is required to break the strong metallic bonds

Question 18

Why are metals good conductors (of heat and electricity)

Answer 18

Because the delocalised electrons can move

Question 19

Why can metal conduct heat

Answer 19

The moving electrons carry thermal energy

Question 20

Why can metals be bent and shaped

Answer 20

The layers of atoms are able to slide over each other

Question 21

What is an alloy

Answer 21

A mixture of metals

Question 22

Why are alloys harder than pure metals

Answer 22

The different sizes of atoms distort the layers making it more difficult for them to Slide Over each other

Question 23

What are electrostatic forces

Answer 23

Strong forces of attraction between ions

Question 24

Properties of ionic compounds

Answer 24

• very high melting and boiling points as the strong electrostatic forces require a great deal of heat energy to break
• cannot conduct electricity when solid because the ions can’t move (they are locked in place by strong electrostatic forces of attraction)

Question 25

Why can ionic compounds conduct electricity when they are melted or dissolved in water

Answer 25

The IONS can now move and carry the charge (not the electrons)

Question 26

Features of a solid

Answer 26

- extremely hard to compress (particles are packed together in a regular pattern) - they have a fixed shape and cannot flow from place to place (the particles can vibrate but can’t move from place to place)

Question 27

Features of a liquid

Answer 27

- extremely hard to compress (the particles are close together) - unlike solids, liquids take the shape of their container and flow from place to place (particles in a liquid can move)

Question 28

Features of a gas

Answer 28

- extremely easy to compress (particles are widely spread) | - they spread out and fill the space of their container (the particles move quickly and randomly)

Question 29

the stronger the forces of attraction between the particles…

Answer 29

The more energy needed to break them and the higher the melting point

Question 30

Why does something have a low melting point

Answer 30

The forces of attraction between the particles are relatively weak, making them fairly easy to break

Question 31

Limitations of the simple particle model of solids liquids and gases

Answer 31

- the simple particle model assumes that all particles are solid spheres (particles have different shapes and are not solid) - it is assumed that there are no forces between the particles (forces between particles have a major impact on the melting and boiling point of a substance)

Question 32

What state is aqueous

Answer 32

Dissolved in water (aq)

Question 33

What do ionic compounds form

Answer 33

-Giant structures where every positive ion is surrounded by a negative ion (giant ionic lattice)

Question 34

What do giant ionic lattices have

Answer 34

- Strong forces of attraction between the positive and negative ions (electrostatic forces) - Electrostatic forces are called ionic bonds

Question 35

What are the properties of small molecules (covalent)

Answer 35

- they have low melting and boiling points - they are usually gases or liquids at room temperature - they do not conduct electricity AS the molecules don’t have an overall electric charge

Question 36

Why do small molecules have low melting and boiling points

Answer 36

- because the weak intermolecular forces between the molecules do not require a lot of energy to break

Question 37

What are the atoms in each molecule held by

Answer 37

Strong covalent bonds

Question 38

What does increasing the size of the molecule do (small covalent bonds)

Answer 38

- their boiling point increases as the intermolecular forces increase and require more energy to break

Question 39

Key facts about giant covalent molecules

Answer 39

- always solids at room temp as they have millions of strong covalent bonds - they always have high melting and boiling points

Question 40

What is diamond formed from

Answer 40

Carbon

Question 41

What does each carbon atom form in diamond

Answer 41

- four strong covalent bonds to four other carbon atoms

Question 42

Why does diamond have a high melting and boiling point

Answer 42

- they have a huge number of strong covalent bonds which have to be broken when diamond is melted - this requires a great deal of energy

Question 43

Property of diamond

Answer 43

- cannot conduct electricity as there are no free electrons to carry electrical charge

Question 44

Key fact about silicone dioxide

Answer 44

- very high melting and boiling point | - a huge number of strong covalent bonds must be broken, this takes a great deal of energy