Structures And Bonding

Question 1

What are ions

Answer 1

Electrically charged particles formed when atoms lose or gain electrons

Question 2

What do metal atoms form?

Answer 2

Positively charged ions

Question 3

What do non-metal atoms form?

Answer 3

Negatively charged ions

Question 4

What are ionic bonds?

Answer 4

Strong electrostatic forces of attraction between oppositely charged ions

Question 5

Why are electrostatic forces strong?

Answer 5

The bond between positive (+) and negative (-) is strong as they have

High melting and boiling points so a lot of energy is needed to break the bonds

Question 6

If an atom loses an electron how do you draw it?

Answer 6

Remove one electron from the outer shell

Chuck a bracket around it

Give it a cheeky plus (+) sign next to it

Question 7

If an atom loses more than one electron how do you draw it?

Answer 7

Remove the electrons from the diagram

Chuck a bracket around it

Write however many electrons lost with a plus (+) sign after it

Question 8

If an atom gains an electron, how do you draw it?

Answer 8

Add an electron

Chuck a bracket around it

Write a minus (-) sign next to it

Question 9

If an atom gains more than one electron, how do you draw it?

Answer 9

Add however many electrons

Chuck a bracket around it

Write however many electrons it gained next to it next to a minus sign

Question 10

Sodium + chlorine > …..

Answer 10

Sodium chloride

Question 11

Properties of ionic substances (4)

Answer 11

High melting point

Allow electric current

Does not produce a molecule

Dissolves in water

Question 12

Properties of covalent substances? (2)

Answer 12

Low melting point

No electric current

Question 13

What is a lattice?

Answer 13

A giant structure

Question 14

What are electrostatic forces?

Answer 14

They hold oppositely charged ions together

Question 15

What are covalent bonds?

Answer 15

Strong bond between 2 non metal atoms. It consists of a shared pair of electrons

Question 16

What covalent bonds can molecules have?

Answer 16

Single

Double covalent bond (O=O)

Triple covalent bond (nitrogen)

Question 17

Why do covalent bonds have low melting and boiling points?

Answer 17

The intermolecular forces are weak

Question 18

What is an isotope ?

Answer 18

Atoms with the same amount of protons but different amount of neutrons

Question 19

What are the relative masses of the 3 main sub atomic particles?

Answer 19

Electron = 1/1840
Proton= 1
Neutron = 1

Question 20

How do you draw covalent bonds?

Answer 20

Dot and cross diagram

Two interlocking circles with dots for one set of atoms and crosses for the other

Question 21

Properties of simple molecular substances ?

Answer 21

Low melting and boiling points

Because of

Weak intermolecular forces

They have strong covalent bonds

They don’t conduct electricity

Question 22

What are the two main types of covalent bonds?

Answer 22

Simple molecules

Giant covalent structures

Question 23

Example of simple molecular structures?

Answer 23

CO2

Question 24

What happens when simple molecular structures are heated?

Answer 24

They have strong bonds between atoms and weak intermolecular forces

The intermolecular forces break

Question 25

What are giant covalent structures?

Answer 25

High melting and boiling points | Many atoms joined together to form a giant lattice

Question 26

3 main types of macromolecules (giant covalent)?

Answer 26

Diamond Graphite Silica

Question 27

Properties of graphite ? (4)

Answer 27

Has gaps and layers The layers can slide over eachother of weak intermolecular forces between the layers. This makes them soft Has free delocalised electrons which allow an electric current to flow One carbon atom is joined to 3 others

Question 28

Properties of diamond? (3)

Answer 28

The atoms are bonded together in a rigid network There This makes it hard and solid It does not conduct heat and electricity as There aren't any delocalised electrons Each carbon atom in joined to 4 others

Question 29

What is graphite used for?

Answer 29

Lubricants

Question 30

Why do giant covalent structures have high boiling points ?

Answer 30

Strong covalent bonds must be broken

Question 31

What is silica?

Answer 31

Similar structure to diamond but contains silicon and oxygen instead of carbon atoms Found in sand

Question 32

Metallic structure properties?

Answer 32

High melting and boiling points Positive ions in a sea of pDelocalised electrons so can conduct electricity Malleable Strong attraction between ions and delocalised electrons

Question 33

Properties of giant ionic structures?

Answer 33

High melting points Strong electrostatic attraction between positive and negative ions

Question 34

What are the two types of polymers?

Answer 34

Thermosoftening Thermosetting

Question 35

What are thermosoftening polymers? 2 and example

Answer 35

Example- polyethene Soft and melt because forces between chains are weak Chains do not join together

Question 36

What are thermosetting polymers?

Answer 36

Example - melanine Joined together by cross links Hard and rigid Do not soften when heated and can't be re shaped

Question 37

When can ionic compounds conduct electricity and why?

Answer 37

When they are melted or dissolved in water Ions are free to move and carry current. They can't conduct electricity when solid because ions can't move around in their lattice structure

Question 38

What are alloys

Answer 38

Mixture of two or more elements Used to make a metal harder

Question 39

What are shape memory alloys?

Answer 39

They return to their original shape after being bent Used in dental braces

Question 40

Properties of nanoparticles?

Answer 40

Large surface area to volume ratio Used in Sunscreens to block ulterviolet light without being visible on skin New catalysts New computers

Question 41

What are fullerenes?

Answer 41

Cages and tubes with different number of carbon atoms Used in lubricants and as catalysts Tube fullerenes are called nanotubes