Topic 2 - Bonding, Structure and Properties of Matter

Question 1

How do you predict a substance’s state?

Answer 1

Below MP = Solid
Above BP = Gas
In the middle = Liquid

Question 2

What are ions?

Answer 2

Ions are charged atoms which have either lost or gained an electron

Question 3

Why do atoms gain or lose an electron?

Answer 3

They do this because they are trying to gain a full outer shell like a noble gas

Question 4

Why do ionic bonds form?

Answer 4

Because oppositely charged ions are strongly attracted to one another by electrostatic forces to form an ionic bond

Question 5

Do ionic compounds have a low or high MP and BP and why?

Answer 5

They have a high MP and BP because a greater amount of energy is needed to overcome the strong attraction between a particles

Question 6

Why can ionic compounds conduct electricity when molten but not when solid?

Answer 6

This is because when they are solid they are in a fixed position and cannot carry a charge contrasted with being molten and able to move

Question 7

Which groups form ions most readily and why?

Answer 7

Elements on groups 1,2,6 and 7 will most readily form ions because they only need to gain or lose 1/2 electrons to have a full outer shell

Question 8

What do you use dot and cross diagrams for?

Answer 8

They show the number of electrons in an atom and how they change during a reaction

Question 9

What type of atoms form covalent bonds?

Answer 9

Only non-metal atoms form covalent bonds with one another

Question 10

Why do covalent bonds form?

Answer 10

They form covalent bonds in order to achieve a full outer shell

Question 11

How do covalent bonds form and why are they so strong?

Answer 11

They form because two atoms share electrons, they are so strong because the nuclei of the atom is attracted to the electrons by electrostatic forces which are hard to overcome

Question 12

Why don’t covalent bonds conduct electricity?

Answer 12

They do not have any delocalised or free moving particles that can carry charge within them

Question 13

What is an allotrope?

Answer 13

Different structural forms of the same element in the same physical state

Question 14

Define aqeous

Answer 14

It means ‘dissolved in water’

Question 15

What are ionic compounds and what is their structure?

Answer 15

Compounds which only contain ionic bonds on the structure of a giant lattice

Question 16

Why are ionic compounds so strong?

Answer 16

They have strong electrostatic forces in all directions

Question 17

What are ions?

Answer 17

Charged particles

Question 18

T/F: Metals lose an electron and non-metals gain electrons

Answer 18

True

Question 19

What is a polymer and how are they bonded?

Answer 19

Polymers are long strings of repeating units which are joined by covalent bonds

Question 20

Why do polymers have a lower MP and BP than giant covalent structures of ionic lattices?

Answer 20

This is because whilst the individual units are joined by strong covalent bonds, the whole structure is held together by weaker intermolecular forces

Question 21

What are fullerene nanotubes and what are they used for?

Answer 21

These are tiny carbon cylinders which are great thermal and electrical conductors, they are tensile (don’t break when stretched); they are used in electronics to add strength without adding weight

Question 22

What are fullerenes and what are they used for?

Answer 22

These are tubes of carbon in the shape of hexagons, pentagons or heptagons, these cages can form around other molecules and trap them inside (.e.g. tablets); they are great catalysts and effective lubricants

Question 23

What is graphene and what is it used for?

Answer 23

This is just one layer of graphite meaning that it is one atom thick and 2D, ot can be added to materials to strengthen them without adding much weight; it can also conduct electricity thanks to delocalised electrons

Question 24

What is graphite and what is it used for?

Answer 24

Each carbon forms three covalent bonds meaning there is one delocalised electron and graphite can conduct electricity, they form layers in hexagons and because there are no covalent bonds between layers it is soft and slippery

Question 25

What is diamond and what is it used for?

Answer 25

Diamonds is the hardest naturally occurring substance known to man, this is because it forms 4 covalent bonds so it also has no delocalised electrons to conduct electricity

Question 26

What is silicon dioxides more common name and what is it made up of?

Answer 26

Commonly known as sand it is a giant structure of silicon and oxygen to form sand

Question 27

What are the scientific names for positive ions and negative ions?

Answer 27

Positive ions = cations

Negative ions = anions

Question 28

What is an alloy?

Answer 28

A mixture of two or more metals or a metal with another element

Question 29

Why do we use alloys?

Answer 29

Adding another metal or element can enhance the properties of the original metal .e.g. adding iron to make something stronger

Question 30

What are nanoparticles?

Answer 30

They are very, very, very, very small particles

Question 31

What is an important property of nanoparticles that is useful in reactions?

Answer 31

They have a large surface area to volume ratio, so they can be small but have a large SA

Question 32

What can nanoparticles be used for?

Answer 32

Cosmetics (moisturiser), catalysts, silver nanoparticles have antibacterial properties, some can conduct electricity