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Revision for C1
C1 1 Fundamental ideas
C1 2 Rocks and building materials
C1 3 Metals and their uses
C1 4 Crude oil and fuels
C1 5 Products from oil
C1 6 Plant oils
C1 7 Our changing planet
C1 1.1, 1.2 and 1.3
Atoms are made up
of protons,
neutrons and
electrons.
Nucleus
Particle
Charge
Mass
Proton
+1
1
Neutron
0
1
Electron
-1
0
Electrons are arranged in
energy levels (shells).
The fourth shell can hold 18
electrons (but you don’t
The first shell can hold 2
need to go that far).
electrons.
The second shell can
hold 8 electrons.
Electron configurations can
be written 2,8,8,18.
The third shell can hold 8
electrons.
All atoms want a full outer
shell of electrons, and they
will do that by gaining
electrons, losing electrons
or sharing electrons.
C1 1.4 Forming bonds
A metal atom gives electrons to a non-metal atom, so that both of them have full outer shells.
When drawing the electron configuration for an
ion, we draw square brackets around it, and put
the charge on the outside.
Electron configurations can be
written Na [2,8]+ and Cl [2,8,8]-
-
+
Na
Cl
We draw the electrons as
different shapes to show
which atom they came
from (dot and cross
diagrams)
Charges on ions from different groups
Group
Outer shell electrons
1
1
2
2
3
3
4
4
Electrons gained/lost
Loses
1
Loses
2
Loses
3
N/A
Ion charge
+
2+
3+
N/A
5
5
6
6
7
7
Gains 3 Gains 2 Gains 1
3-
2-
-
8
8
N/A
N/A
C1 1.4 Forming bonds
If the positive and negative ions have different charges, then you will need different
numbers of ions to balance out the charge e.g. MgF2.
Mg
F
Remember: Swap n’ drop
Swap the ion charge numbers, and drop
them down to the bottom right of the
element symbol. Get rid of the charge.
These ions are on your data sheet, so you
don’t need to remember them.
Mg2+
MgF2
F-
-
2+
F
Compound ions
If your compound has a compound ion
(OH-, NO3-, SO42-, CO32-, NH4+) and there is
more than one of them, you need to put
it in brackets.
E.G Mg(NO3)2, or (NH4)2O, or Al2(SO4)3
C1 1.4 Forming bonds
Covalent bonding is a shared pair of electrons.
Covalent bonding occurs between non
metals.
covalent bond
F
simplified
dot and
cross
diagram
solid line
(one line
= 1 pair)
Group 4 elements share 4 electrons.
Group 5 elements share 3 electrons.
Group 6 elements share 2 electrons.
Group 7 elements and hydrogen share 1
electron.
F
H
F
F
N
H
O
H
H
H
F–F
F
–F
H
Cl
O
C
O
Balancing equations
+
+
CH4 + 2O2  CO2 + 2H2O
There are 4 hydrogens here.
You multiply the big number
by the little number.
There are 4 hydrogens here,
bonded together.
There are 2 molecules of
oxygen not bonded together.
You can only change the BIG numbers in equations – we cannot change the small numbers
or add or take away any reactants or products.
C1 2.1 Limestone and its uses
Carbon dioxide is formed from thermal
decomposition of limestone and from burning
methane.
Argon and nitrogen come from the air.
Calcium
oxide
Calcium
carbonate
CaCO3

CaO +
Carbon
dioxide
CO2
Reaction of thermal
decomposition
limestone.
Methane is fuel
for the fire to
heat limestone.
C1 2.2 Reactions of carbonates
CaCO3(s)  CaO(s) + CO2(g)
CaO(s) + H2O(l)  Ca(OH)2(s)
Ca(OH)2(s)  Ca(OH)2(aq)
Ca(OH)2(aq) + CO2(g)  CaCO3(s) + H2O(l)
Limestone is heated and
breaks down (thermal
decomposition) into calcium
oxide (quicklime) and carbon
dioxide.
Calcium oxide (quicklime) is
added to water to make solid
calcium hydroxide (slaked
lime).
Solid calcium hydroxide
(slaked lime) is dissolved in
water to make aqueous
calcium hydroxide (lime
water).
Aqueous calcium hydroxide
(lime water) is added to
carbon dioxide which makes
calcium carbonate and water.
C1 2.3 Limestone reaction cycle and C1 2.4 cement and concrete
+
Sand
+
Sand
+
Water
+
Gravel
Concrete
Cement
+ Clay
+
Limestone
Water
Mortar
CaO
Calcium Carbonate
CaCO3
HEAT
Calcium Oxide
+
+ Water
Calcium Hydroxide
Limewater
Ca(OH)2
Carbon Dioxide
CO2
C1 2.5 Limestone issues
Limestone quarrying has many advantages
and disadvantages:
Advantages
It creates jobs
It provides building materials nearby
Disadvantages
Pollution
Noise pollution
It ruins the landscape
C1 3.1 Extraction of metals
Extracted using
electrolysis.
Extracted using
reduction by
carbon.
Found as
elements
(native).
Reduction is a reaction that
removes oxygen from the
metal oxide.
Carbon + oxygen  Carbon dioxide
C + O2 
CO2
C1 3.2 Extraction of iron
Carbon dioxide + carbon  Carbon monoxide
CO2
+ C

2CO
Iron oxide + carbon monoxide  Iron + carbon dioxide
Fe2O3 +
3CO
 2Fe +
3CO2
Iron oxide + carbon  Iron + carbon dioxide
2Fe2O3 + 3C  4Fe +
3CO2
The iron produced in the blast furnace is 4% carbon. This is called pig
iron.
Pure iron is arranged in layers . When an
atom is struck, the whole layer moves.
Pure iron is malleable.
Pig iron is very brittle because the atoms
are not in layers due to the carbon atoms
disrupting the layers.
Steel
Low carbon steel
High carbon steel
Low alloy steels
High alloy steels
Stainless steels
Tungsten steel
Composition
Uses
Iron, carbon (0.1%) Cars, buildings
and bridges
Iron, carbon (1.5%) Tools, knives and
swords
Iron, carbon,
Cars, trucks,
manganese, nickel bridges
Iron, carbon,
Tools, armour
chromium
Iron, carbon,
Cutlery,
nickel, chromium
saucepans,
medical
instruments.
Iron, carbon,
Drill bits
tungsten
Pure iron is arranged in layers . When an
atom is struck, the whole layer moves.
Pure iron is malleable.
C1 3.2
Steels
Steels are mixtures of iron,
carbon and possibly other
metals. Steels are alloys.
Alloys are stronger than
pure metals because they
disrupt the layers of the
metals and stop them
sliding over each other.
The layers of alloys are disrupted, so they
stop the layers of metal atoms sliding over
each other.
C1 3.3
Aluminium and titanium
Aluminium is too reactive to extract
from its ore using carbon, so it is
extracted using electrolysis.
Aluminium is light and strong. It is
used for aircraft, foil, drinks cans,
saucepans and bicycles.
Titanium is not reactive, but if
carbon is used to displace it, it will
form brittle titanium carbide.
Instead, titanium oxide is reacted
with chlorine to make titanium
chloride. It is then reacted with
sodium to make titanium. This is
expensive as the sodium needs to be
extracted using electrolysis.
C1 3.4 Extraction of copper and C1 3.6 metallic issues.
Copper sulphide + oxygen  Copper + sulphur dioxide
This is called smelting. Sulphur dioxide causes
acid rain.
The copper then undergoes electrolysis
in order to purify it.
Copper can also be extracted by phytomining.
Plants take up copper from the soil. The plants are
then burnt and the ashes are put in sulphuric acid.
Scrap iron is added to the copper sulphate to displace
it.
Iron + copper sulphate  Copper + iron sulphate
Copper can also be extracted by bioleaching.
Bacteria feed on copper ores to get copper solutions.
These solutions are also reacted with iron to extract the
copper.
Iron + copper sulphate  Copper + iron sulphate
C1 chapter 3.5 Useful metals and C1 3.6
metallic issues.
They have the following
properties:
Shiny
Malleable
Hard
Strong
High melting point
Sonorous
Conducts electricity
Conducts heat
It is good to recycle metals
because it saves energy from
extracting them. It reduces
pollution as the vehicles are no
longer needed to excavate them
and it means that less ore is used
up.
C1 chapter 4.1 Crude oil
Crude oil is a mixture of lots of different chemicals
called alkanes.
Alkanes only contain
hydrogen and carbon
(hydrocarbons) an they
have all single bonds (they
are saturated) and have a
general formula of CnH2n+2.
C1 4.1 Alkanes
Shorter chain alkanes have:
Longer chain alkanes have:
Lower boiling points.
Higher boiling points.
Low viscosity.
High viscosity.
High flammability.
Less flammability.
C1 4.2
Fractional distillation
In fractional distillation,
crude oil is heated up.
Smaller alkanes have lower
boiling points and they go
to the top.
Larger alkanes have larger
boiling points and they stay
at the bottom.
The crude oil is split into
fractions. Each fraction has
a use.
C1 4.3 and C1 4.4 Burning fuels and Cleaner fuels.
C1 4.5 Alternative fuels
Biodiesel
Biodiesel is fuel from plant or
animal products, such as
vegetable oils or animal waste.
Ethanol
Made by fermenting
sugar from plants.
Advantages
Advantages
• It burns cleanly.
• It burns cleanly.
• It is carbon
neutral.
• It is carbon neutral.
Disadvantages
• It is less harmful to plants
and animals.
• It needs land that
should be used for
Disadvantages
food.
• It needs land that should be
• It destroys
used for food.
habitats.
• It destroys habitats.
Hydrogen
Made from electrolysis
of water.
Advantages
• It burns cleanly.
• Obtained from water
Disadvantages
• Requires electricity.
• Explosive.
• Needs larger volume
to store.
C1 5.1 Cracking hydrocarbons
Alkenes – Alkenes are hydrocarbons (made up of
carbon and hydrogen) with a carbon-carbon double
bond (C=C). They have the general formula CnH2n (2
hydrogens for every carbon).
You can use bromine water to work out if you
have an alkene. Bromine water is brown. Alkenes
make it colourless. Alkanes do not change the
colour (it stays brown).
Cracking – this is when a large alkane is turned into a smaller alkane and an
alkene.
C1 5.2 Making polymers from alkenes
If alkenes are put under a high
temperature and pressure,
then they all link up to form a
long chain called a polymer.
An individual alkene is
called a monomer
(mono = one, mer =
part). When they are
joined together, they
become a polymer (poly
= many)
An individual unit is
in square brackets.
The lines show that it is bonded to
monomers outside the brackets.
n = a big number
C1 5.3 New and useful polymers
Hydrogels are polymers that can
trap water inside them. They can
be used as contact lenses or
dressings for burns.
Stitches can be made from shape
memory polymers which tighten
to just the right tightness to close a
wound. Eventually, when the
wound is healed, they dissolve
away.
Plasters can be made from
light sensitive polymers that
lose their stickiness when
exposed to light. Instead of
ripping the plaster off, you
can just rip the cover off
which makes the plaster fall
away.
C1 5.4 Plastic waste
Landfill
Advantages
Easy
Relatively
cheap
Quick
Disadvantages
Uses up land
The plastics
stay for
centuries
Incineration
Recycling
Biodegradable
plastics
Quick
Saves energy and Saves landfill
The plastics can resources.
space.
be used as fuel.
Preserves crude oil
supplies.
Tropical forests are
destroyed to create
farm land.
Causes
Takes time and
Needs land space
pollution
fuel (to transport to grow crops
and sort).
(reduces land
Recycled plastic is space to grow
never as strong as food)
original plastic.
C1 5.5 Ethanol
Ethanol can be made by fermentation
yeast
Sugar (glucose)
Ethanol + carbon dioxide
C6H12O6
2C2H5OH + 2 CO2
Sugar is a renewable resource, but it needs land to grow, which would
take away land needed to grow food.
Ethanol can also be made by hydration (Adding water to) ethene.
Phosphoric acid catalyst
Ethene + steam
C2H4 + H2O
Ethanol
C2H5OH
Ethene is from crude oil, so this method is non renewable.
It does produce pure ethanol, however.
Ethanol can be used as a fuel or a
solvent.
C1 6.1 Extracting vegatable oil
Plants use energy from the sun to make glucose. They then turn this glucose into
other chemicals, such as vegetable oil.
Chlorophyll
Carbon dioxide + water
6CO2
Sunlight
Glucose + oxygen
C6H12O6 + 6O2
+ 6H2O
Vegatable oils are unsaturated (they have carbon-carbon double bonds). Animal fats are
saturated (they have no double bonds). Vegatable oils are liquids at room temperature.
Animal fats are solids at room temperature.
Animal
fat
Vegetable
oil
Animal
fat
Vegetable oil
C1 6.2 Cooking with vegetable oils
Cooking things in oil (compared to cooking things
in water) cooks them more quickly (because oil
has a higher boiling point), makes the outside of
the food change colour and crispier, and makes
the inside softer.
vs
Cooking in water.
Cooking in oil.
Foods cooked in oil have more energy than foods
cooked in water.
Hydrogenation of vegetable oils
Hardened
vegetable oil
Unsaturated
vegetable oil
H
C
H
C
H
H
C
H
C
H
Nickel
+H
H
60oC
C1 6.3 Everyday emulsions
When water and oil
mix, little droplets of oil
form in the water. This
mixture is called an
emulsion.
We use emulsifiers to help oil and
water mix. Emulsifiers have two
parts –a head that mixes with
water (hydrophilic) and a tail that
mixes with oil (hydrophobic).
However, water and oil
do not mix easily (they
are immiscible), so they
end up like this.
This is how emulsifiers help oil and water mix.
Oil
Emulsifiers can be
used to help make
mayonnaise and
detergents to help
wash up oily pans.
Water
C1 6.4 Food issues
A food additive is a substance that is added to a food
to improve its taste, preserve it or change its colour.
All food additives in our food have an E number to
prove that they have passed a safety standard.
Emulsifiers have an E number that begins with 4.
Emulsifers stop oil and water based substances from
separating. Emulsifiers are needed in chocolate,
mayonaise and ice cream. So emulsifers make foods
with lots of energy easier to eat and so it is tempting
to eat more fatty food.
vs
Vegetable oils are healthier than
animal fats. They contain vitamin E
and they are better for the heart
than animal fats.
C1 7.1 Structure of the Earth
Atmosphere
Crust
About 100km from
5 – 70km thick
the surface to the top.
Mantle
3000km thick
Core
3500km in diameter
Made of 78%
Made of rock. We get
nitrogen, 21% oxygen, minerals from the
1% argon and 0.04% crust and the oceans.
carbon dioxide. We
collect the gases from
the atmosphere to
use.
Semi liquid. It can
flow very slowly. The
crust floats on top of
it.
Made of iron and
nickel. The outer part
is liquid due to the
high temperature and
the inner part is solid
due to the high
pressure.
We know what the
inside of the earth is
like from earthquake
data. The way the
earthquake waves
bend tell us the density
of the substances
below the surface.
C1 7.2 The restless Earth
The Earth’s crust is split into sections called
plates. The plate boundaries are where we find
earthquakes, volcanoes and mountains.
Mountains form when two plates move together.
Earthquakes occur when two plates rub side by
side.
Plates move because they are floating on top
of the semi-liquid mantle. Radioactive
processes in the mantle release heat which
make convection currents which make the
plates move.
Alfred Wegener came up with the theory of plate tectonics. His evidence was that
fossils and rocks on different continents were similar, indicating that they were
once joined. However, this was also supported by the idea of a land bridge which
connected South America and Africa. His theories were not accepted until 50 years
later when scientists discovered something called seafloor spreading.
C1 7.3 The Earth’s atmosphere in the past
4 Billion years ago
Earth’s atmosphere was
mainly carbon dioxide,
with methane, water
vapour, nitrogen and
ammonia.
4 billion years ago
3.4 Billion years ago
The oceans are formed
when water vapour
condensed.
Life was formed. It was
bacteria that used undersea
volcanoes as a source of
food.
2.5 Billion years ago
Algae evolved which
could use
photosynthesis to
make food from gases
in the atmosphere.
200 million years ago
The Earth’s
atmosphere is the
same as what it is
today.
600 million years ago
2.5 Billion years ago
Animals evolved which
could use the oxygen
for respiration.
The oxygen in the atmosphere
reacts with the methane and the
ammonia in the atmosphere.
C1 7.4 Life on Earth
The Miller-Urey experiment took
place in 1953. The scientists took
the substances that were in the
atmosphere billions years ago. They
used water, methane, ammonia and
hydrogen and passed an electric
spark through them. They got 11
amino acids.
C1 7.5 Gases in the atmosphere
Carbon dioxide
has been ‘locked
into’ rocks such
as limestone.
Ammonia and methane in the
atmosphere reacted with
oxygen to form carbon dioxide,
water and nitrogen.
CH4 + 2O2  CO2 + 2H2O
4NH3 + 3O2  2N2 + 6H2O
The gases in the atmosphere
can be removed by fractional
distillation. The gases are
cooled to a temperature
below -200oC and gradually
heated up. Nitrogen boils off
first at -196oC.
C1 7.6 Carbon dioxide in the atmosphere
The carbon cycle
issolves
hotosynthesis
Respirati
on
lants
espiratio
n
nimals
alcium
arbonate
Sedimentation
Sedimentation
imestone
Since the 1960s, the amount of carbon dioxide in the
atmosphere has increased. This may be due to burning fossil
fuels. Some of the carbon dioxide is absorbed into the oceans.
This makes them more acidic, which reacts with coral reefs.