C2 Bonding, structures and states of matter

Question 1

what are the properties of solids

Answer 1

particles are in a fixed shape, state symbol (s), fixed shape and volume

Question 2

what are the properties of liquids

Answer 2

state symbol (l), changes shape in different containers, particles can flow over eachother but are still attracted to eachother.

Question 3

what are the properties of gases

Answer 3

state symbol (g), particles are free to move, can be easily compressed, expands to fill shape of container

Question 4

what is the state symbol (aq)

Answer 4

aqueous, something dissolved in water

Question 5

what is the process from solid to gas

Answer 5

sublimation

Question 6

what is the process from gas to solid

Answer 6

deposition

Question 7

what are the limitations of the particle model?

Answer 7

The simple particle model assumes that particles are solid spheres.
In most substances the particles are atoms, molecules or ions, and not solid spheres.
Atoms, molecules or ions vary in size - in particle theory they are represented as equal in size.
Particle theory diagrams do not show that there are forces or bonds between the particles.
Atoms are mostly empty space so real particles are not solid at all!

Question 8

what are the two types of atoms?

Answer 8

metal and non metal

Question 9

what do metals do when forming an ion?

Answer 9

metals loose elctrons when froming ions, they form postitive ions

Question 10

what do non metals do when forming ions?

Answer 10

non metals gain electrons when forming ions, they form negative ions

Question 11

how are ionic bonds formed?

Answer 11

ionic bonds are formed with electrostatic attraction

Question 12

what is the elctrostatic attraction between?

Answer 12

opposite charges, positive metal ions and negative non metal ions

Question 13

how do you work out ionic formulae?

Answer 13

switch the charges of the opposite elements to make it neutral.

Question 14

what do electrostartic attractions hold?

Answer 14

they hold oppositley charged ions in a lattice

Question 15

when are covalent bonds formed?

Answer 15

Covalent bonds are formed when atoms of non-metals share pairs of electrons with each other
each shared pair of electrons is a covalent bond

Question 16

for covalent bonding you only show the ……… shell

Answer 16

outer

Question 17

Explain the bonding in lithium fluoride

Answer 17

Lithium fluoride is an ionic compound.
A lithium atom loses one electron to make a Li+ ion.
This electron is transferred to fluorine to make a F- ion.
The atoms are held in place by electrostatic attraction between the positive and negative ions,
In a lattice.

Question 18

what do giant ionic lattices have?

Answer 18

Strong electrostatic forces of attraction between oppositely charged ions
So have very high melting and boiling points
Lots of heat energy needed to overcome strong electrostatic forces of attraction

Question 19

what are molten ionic compounds?

Answer 19

Cannot conduct electricity when solid - ions are in fixed positions
When molten the electrostatic attraction has been overcome
Ions able to move and carry the charge

Question 20

what are ionic compound solutions?

Answer 20

Ions separate and interact with water molecules
Ions are free to move and carry the charge

Question 21

What makes copper a good material for a wire?

Answer 21

Good conductor of electricity

Malleable - able to be hammered or pressed into shape without breaking or cracking.

Ductile - able to be drawn out into a thin wire.

Question 22

what is metallic bonding?

Answer 22

2 or more metal atoms, giant structure of atoms, delocalised electrons free to move throughout structure, delocalised electrons carry current, positive metal ions, malleable layers can slide over each other

Question 23

Explain why metals conduct electricity

Answer 23

the atoms are arranged in a giant structure, delocalised electrons are free to move throughout the whole structure.

Question 24

what is an alloy?

Answer 24

An alloy is a mixture which contains at least one metal.

Question 25

what is the difference between a metal and an alloy?

Answer 25

metal:
atoms can slide
same size
softer

alloy:
atoms different sizes
layers cant slide
stronger and more brittle

Question 26

suggest why conductivity increases across the periodic table from sodium to magnesium to aluminium (4)

Answer 26

from left to right across the period, atoms of elements have more free electrons, because they have more electrons in the outer shell

Question 27

what are the properties of diamond?

Answer 27

Each C atom is covalently bonded to 4 other C atoms
Bonds are strong
Large number of bonds
High melting point and very hard - difficult to break the strong bonds
Cannot conduct electricity
Uses: cutting tools, e.g. drill bits

Question 28

explain why diamond has a high melting point?

Answer 28

there are large numbers of covalent bonds, between atoms, the covalent bonds are strong

Question 29

what are the properties of graphite?

Answer 29

Each C atom is covalently bonded to 3 other C atoms
One unpaired electron which is free to move between layers
Weak intermolecular forces between layers - soft as layers slide
Large number of bonds
High MP - difficult to break the strong bonds
Can conduct electricity due to free electron movement throughout structure
Uses: pencil (layers slide), lubricant, electrodes

Question 30

why can graphite be used in the leads of pencils?

Answer 30

because graphite is made of layers of carbon atoms, that have weak forces of attraction between layers, so the layers can slide off each other and the layers can peel off

Question 31

why can graphite be used as an electrical conductor?

Answer 31

each carbon atom has 3 covalent bonds, which means there are free electrons to move

Question 32

what are the features of graphene?

Answer 32

one atom thick, thin and flexible, 3 covalent bonds per atom of carbon, each atom has one unpaired, delocalised electron so good conductor of electricity, giant structure, strong covalent bonds, high melting point, light weight

Question 33

what are the uses of graphene?

Answer 33

electronic screens,

Question 34

what are the features of spherical fulurene?

Answer 34

covalent bonds, 3 carbon bonds for each atom, weak inter molecular forces between spheres, high tensile strength, large structure, does not conduct electricity, electrons do not move out, high melting point.

Question 35

what are the uses of spherical fulurene?

Answer 35

pharmaceutical delivery in the body
lubricants in machines to stop moving parts grind together
catalyst speed up chemical reactions

Question 36

what are the features of cylindrical fulurene?

Answer 36

nano tubes, hollow, strong many covalent bonds, does conduct electricity because of delocalised electrons, strong, high tensile strength (can be stretched without breaking)

Question 37

what are the uses of cylindrical fulurene?

Answer 37

deliver drugs and electronics, tennis rechets

Question 38

why does graphene conduct electricity?

Answer 38

each carbon atoms has an unpaired electron, the electrons are delocalised

Question 39

why would graphene would not be suitable for a touch screen?

Answer 39

the layers would slide

Question 40

how many carbon atoms does buckminstersfullurne have

Answer 40

60