Download H 2 - Wildern VLE

What is crude oil?
http://www.youtube.com/watch?v=PYMWUz7TC3A
Something that
•Crude oil is a fossil fuel (non renewable) takes along time to
make and is used
•All the readily extractable resources will be used
up faster than it is
up in the future
made.
•Need to find replacements
20˚C
•Conflict between making petrochemicals and fuels
LPG
Fractional distillation
Petrol
Crude oil can be separated into it’s useful fractions as
they have different boiling points
The longer chain
hydrocarbon has the
higher boiling point
because the
intermolecular forces
are stronger between
long chain
hydrocarbons
compared to short
chain hydrocarbons.
Naphtha
Paraffin
Diesel
Lubricating oils
Fuel Oil
600˚C
Bitumen
Problems – Exploitation of oil
•
1.
2.
•
1.
2.
Environmental –
transportation
Damage to bird’s
feathers causing death
Use of detergents to
clean up oil slicks and
consequent damage to
wildlife
Political
UK dependent on oil and
gas from politically
unstable countries
Future supply issues
Supply must meet demand
Cracking
Picking the right fuel
Toxicity
Energy value
Availability
Cost
U sability
P ollution
Storage
Complete combustion
Why is the amount
of fossil fuels being
burnt increasing?
• Increasing world population
• Growth of use in developing
countries
CH4 + 2O2
CO2 + 2H2O
Incomplete combustion (some oxygen)
CH4 + 1½O2
CO + 2H2O
Incomplete combustion (little oxygen)
CH4 + O2
C + 2H2O
Composition of CLEAN AIR
Gas
Nitrogen
%
78
Oxygen
Carbon Dioxide
Other
21
0.035
<1
CO2 produced by = taken in by
Photosynthesis
Respiration
PROBLEM – Burning Fossil Fuels
Deforestation
Forming the atmosphere
2.11
http://www.youtube.com/watch?v=6Db2WAG-VVs
Degassing of Early
volcanoes = atmosphere of
H2O and CO2
Earth cools and water
condenses forming
oceans
CO2 dissolves in oceans
Increase in N2 due to
lack of reactivity
Development of
photosynthetic
organisms
Increase in O2 levels
due to photosynthesis
Pollution
Photochemical smog
Oxides of nitrogen – from
petrol engines
In car engine: O2+N2  2NO
Acid
Sulphur in fossil fuels – coal and oil
Rain Oxides of nitrogen – from petrol
engines
Carbon monoxide
Incomplete combustion of petrol and diesel
in cars, lorries and buses
Catalytic converters
2CO + 2NO 
REMOVE CO
N2 +
2CO2
HYDROCARBONS
Alkanes : CnH2n+2
SATURATED-only single
covalent bonds between
carbon atoms.
Each carbon has 4 bonds -
Alkenes:CnH2n UNSATURATED
-at least one double bond
between carbon atoms.
- - Each hydrogen one bond
CH4
Ethene
C2H4
Butene
C3H6
Butane
Propane
Pentane
C2H6
C3H8
C4H10
C5H12
Hexane
C6H14
Methane
Ethane
Propene C4H8
Pentene C5H10
Hexene
C6H12
Test for UNSATURATION – Add
Bromine Water : Orange Colourless
Polymerisation
Monomer
ADDITION POLYMERISATION
Polymer
High Temperature
Catalyst
poly(propene)
THERMOPLASTIC
Weak INTERMOECULAR FORCES
Low melting pt
Easily Stretched
THERMOSETTING
Strong (covalent or cross links)
FORCES
High Melting pt
Rigid
Gore-tex – nylon laminated with PTFE/polyurethane
membrane
Rain water;
Won’t fit through the
holes.
Gore-tex;
Has millions of tiny
holes in it.
Sweat;
Will fit through
the holes.
Membrane too
fragile without
Nylon
SKIN
Cooking
Protein (egg)
Denatured – permanently
changes shape
ADDITIVES
Antioxidants
Food Colour
Flavour enhancer
Emulsifier
Hydrophobic Hydrophilic
Water hating
attaches to oil
Water
loving
attaches to
water
molecules
MIXTURE = EMULSION
Potatoes
Easier to digest 1. cell walls rupture
resulting in loss of rigid
structure and a softer
texture
2. starch grains swell up
and spread out.
Baking Powder
Carbon +
Sodium
+
sodium
dioxide
carbonate
hydrogencarbonate
water
2NaHCO3
Na2CO3 + CO2 + H2O
catalyst
Making esters
alcohol + organic acid → ester + water
sulfuric acid
methanol + butanoic
acid
→
methyl + water
butanoate
Volatile liquids evaporate easily.
Weak attractive forces between particles –
easy to overcome attraction
Why does water NOT remove nail varnish?
•water-water attraction stronger than waternail varnish attraction
•Nail varnish attraction stronger than waternail varnish attraction
Paint is a colloid http://www.youtube.com/watch?v=6BLVuoUmr94 mute
Solid particles are mixed and dispersed with particles of a
liquid but are not dissolved.
Solvent – liquid that suspends the other ingredients so it
can be applied to a surface. It evaporates quickly
so that the paint dries.
Binding medium- Sticks pigment to the surface
Pigment – colour suspended in the solvent.
Paints to dry the
solvent must
evaporate.
Emulsions paintthe solvent is
water.
Thermochromic - Paints which change
colour with a change in temperature
Acrylic paints can be added to give
more of a range of colour changes
Oil Paint
Oil is oxidised by
Oxygen
Phosphorescent - absorb
and store energy and
release it as light over a
period of time. (safer)
The Structure of the Earth
•Lithosphere – relatively cold and
rigid outer part of the Earth
(crust and upper part of the
mantle)
•Tectonic plates less dense than
the mantle
•Mantle = cold and rigid just below
the crust, hot and non-rigid at
greater depths (able to move)
THEORY OF PLATE TECTONICS
•Energy transfer involving convection
currents in the semi-rigid mantle
cause the plates to move slowly.
•Oceanic crust is more dense than
continental crust
•Collision – leads to subduction and
partial melting
•Plates cooler at ocean margins so sink
and pull plates down
Development of Theory of plate
tectonics
Wegener’s continental drift theory
(1914) was not accepted by scientists
at the time. New evidence in 1960s –
show ocean floor spreading. The
theory was slowly accepted as
subsequent research supported the
theory
http://www.youtube.com/watch?v=hhxjAAn
wNKM
Volcanoes
•runny lava – fairly safe produce iron-rich Basalt
•thick lava – violent/explosive
– produce silica-rich Rhyolite
•Geologists study volcanoes gather info. about Earth’s
structure.
•Live near - volcanic soil very
fertile.
Igneous rocks
Slower molten rock cools=
larger crystals
Difficult to study the structure of the
Earth:
•crust too thick to drill all the way
through
•Scientists study seismic waves made by
earthquakes or man-made explosions.
Material
How it is made
aluminium and iron
metals obtained from ores
brick
made from clay
glass
made from sand
cement and concrete
made using limestone
granite, limestone and
marble
rocks mined or quarried
from the ground
•Limestone – sedimentary
•Marble – metamorphic – limestone
put through high temp. and
pressure
•Granite - igneous
Thermal Decomposition of Limestone
calcium carbonate
calcium oxide + carbon dioxide
CaCO3
CaO + CO2
Limestone + Clay = Cement
Cement + sand + water + aggregate = concrete
Reinforced concrete = composite
material – concrete + steel.
Hardness
Flexibility and
strength
Smart Alloys
Smart alloys have unusual properties.
Nitinol = nickel + titanium
shape memory alloy - bent out of shape,
returns to original shape when heated or
electric current passed through it
Electrolyte = Cu(II)SO4(aq)
alloy
main
metal(s) in
alloy
typical use
amalgam
mercury
dental fillings
brass
musical
copper and
instruments,
zinc
coins
solder
joining
electrical
lead and tin
wires and
components
Iron Vs Steel
Steel = harder, stronger,
less likely to rust
Salt
iron + water + oxygen → hydrated iron(III) oxide
Property
Iron
Aluminium
density
high
low
magnetic?
yes
no
corrodes easily?
yes
no
Recycling
EU law – 85% of car’s materials be recycled, >95%
by 2015.
Reduces amount of waste + natural resources used
Hydrogen + nitrogen
3H2(g) + N2(g)
Material
Typical use
Reason for use
steel
body panels and
chassis
strong and
malleable
copper
electrical wiring
good conductor
of electricity
aluminium
Ammonia •450°C
2NH3(g)
•200atm
•Iron catalyst
body panels and lightweight and
interior fittings
rust-proof
glass
windows
transparent
plastics
body panels,
lights and
dashboard
tough and easily
moulded to
desired shape
seats and
carpets
good heat
insulators, and
can be woven
into fabrics
fibres
Acid Rain
Economic considerations
•optimum conditions used - give lowest cost
not necessarily fastest reaction or highest
percentage yield
•rate of reaction and percentage yield - high
enough to make enough product each day.
Production
costs
•energy
•labour
•raw materials
•equipment
•rate of
reaction.
Fertilisers
•Crops grow faster+bigger-crop yields
increased.
•Dissolve in water-absorb them through
roots.
•Essential elements: N P K
Acid + alkali
H+ + OH-
salt + water
H2O
Naming Salts
Chloride - hydrochloric acid(HCl)
Nitrate - nitric acid(HNO3)
Sulphate - sulphuric acid(H2SO4)
Phosphate - phosphoric acid
Making a fertiliser
•measuring cylinder measure volume
of alkali solution
•burette to add acid a little at a time
until the alkali has been neutralised
•filter funnel to remove solid crystals
of fertiliser after evaporating water
from the neutral fertiliser solution
Problems
•too much fertiliser-pollute
Acid + carbonate
salt + water + carbon dioxide water supplies
•Eutrophication - not enough O2
dissolved in water for aquatic
Neutralisation equations
organisms to survive
Bases:NH3, NH4OH, KOH, NaOH, CuO
carbonates: Na2CO3, CaCO3
2Cl– – 2e– → Cl2 (oxidation)
2H+ + 2e– → H2 (reduction)
Hydrogen - manufacture
ammonia and margarine
(used to harden vegetable
oils).
Chlorine •kill bacteria
•make solvents
•make plastics such as
polyvinyl chloride (PVC)
•make household bleach
Ions not discharged make NaOH - used to make soap and household bleach.
sodium hydroxide + chlorine → sodium chloride + water + sodium chlorate
2NaOH + Cl2 → NaCl + H2O + NaClO
http://www.youtube.com/watch?v=gCVbAw6c0Rk
Rate of Reaction
How much product is formed in a fixed
time period (g/s or cm3/s)
Concentration – increases, particles become more crowded
•increase the collision frequency = more successful collisions
•Result = increased rate of reaction.
Temperature – increases, particles gain KINETIC
ENERGY
•move around more quickly/ more energetic
•Particles collide more frequently with more energy
•more collisions per second
•more successful collisions
Pressure - If reactants are gases you can increase the pressure.
•More particles per unit volume.
•Increased collisions frequency
•More successful collisions
•Increased rate of reaction.
Limiting Reactant -reactant that is all used up at the end of the
reaction
•amount of product formed directly proportional to amount of
limiting reactant used.
Rates of Reaction
Catalyst – increases rate of reaction
•Small amount needed to catalyse large
amounts of reactants
•Unchanged at the end of the reaction
Surface Area – larger surface area (smaller particles)
•More frequent collisions
•More successful collisions
•Increased rate of reaction
Fine Combustible powders - An explosion is a very fast reaction which
releases a large volume of gaseous products.
Danger of explosion in factories that handle powdered flammable
substances; custard powder, flour, powdered sulfur.
Reaction finished
Amount of product formed
Faster rate
Slower rate
Rate = gradient = y/x
Relative formula
mass, Mr
16
relative atomic masses
of all the elements in the
compound added
together.
8
Covalent formulae
H2O Water
CO2 Carbon dioxide
NH3 Ammonia
H2
Hydrogen
O2
Oxygen
N2
Nitrogen
SO2 Sulphur dioxide
Conservation of mass in reactions
O
total mass of products =total mass of
the reactants
H H
O
O
H O H
O
C
C
H
O
H
O
O
H O H
Ionic formulae
NaCl
Sodium chloride
CaCl2
Calcium chloride
MgO
Magnesium oxide
HCl
Hydrochloric acid
H2SO4 Sulphuric acid
HNO3 Nitric acid
NaOH Sodium hydroxide
Ca(OH)2 Calcium hydroxide
CaCO3 Calcium carbonate
Al2O3 Aluminium oxide
Fe2O3 Iron oxide
Calculating the mass of a product
Percentage yield
What mass of magnesium oxide is produced
Percentage yield= actual yield x100
when 60g of magnesium is burned in air?
Predicted yield
1. READ the equation:
2Mg + O2
2MgO
Not 100% yield:
•Filtering
2.WORK OUT the relative formula masses (Mr):
•Evaporation
•Transferring liquids
2 x 24
2 x (24+16)
•Not all reactant made into product
48
80
3. LEARN and APPLY the following 3 points:
1) 48g of Mg makes 80g of MgO
2) 1g of Mg makes 80/48 = 1.66g of MgO
3) 60g of Mg makes 1.66 x 60 = 100g of MgO
What mass of hydrochloric acid is needed to
produce 11.1g calcium chloride?
Ca(OH)2 + 2HCl
CaCl2 + 2H2O
Industrial processes want high
percentage yield:
•Reduce wasted reactants
•Reduce cost
Atom economy
The amount of starting materials that become useful products.
• sustainable development
Atom Economy= Mr of desired productx100
• fewer natural resources
Mr of all products
• less waste.
• HOW do you know what is a
useful product?? READ THE
QUESTION
Exothermic Reactions
Heat given out, reactants lose energy.
Endothermic Reactions
Energy / kJ)
Heat taken in, reactants gain energy.
Surroundings get cooler
No bond between atoms
Reactants
Energy level diagram
High in energy.
Products Bonds broken
Products Atoms now
bonded
Reactants Atoms already bonded.
lower in
Progress of reaction
energy
The reactants start with
Progress of reaction
more energy this is lost to the
Energy / kJ)
Energy level diagram
surroundings as heat during
the reaction.
The reactants start with less energy,
they gain energy from the surroundings.
The products have less energy
than the reactants
The products have more energy than the
reactants.
Calorimetry
4.2 J/g/oC
E=mc∆T
Energy supplied
(J)
Fuel Efficiency
(J/g)
Mass of water (g)
Energy supplied (J)
Specific heat
Rise in
capacity of
temperature (oC)
o
water (J/g/ C)
Mass of fuel burnt(g)
Batch process
Measure mass of fuel burnt
Measure ∆T
•Same volume of water
•Same calorimeter
•Same heating time
•Make product on demand
•small scale, Fixed amount
•making drugs that have expire
date.
•Easy to change the product
from one to another.
•Very labour intensive- reactor
needs to be filled emptied and
cleaned.
•high cost per tonne.
•Time needed for cleaning and
t change product line
Continuous process
•24/7
•shut down for
maintenance
•Haber process.
•Automation-few staff
cheaper per tonne.
•less energy to maintain,
as long as the process can
be kept running.
•High set up cost
•Must be used constantly.
Which cooking fuel is best?
Temp before
heating
in C
Temp after
heating
in C
methane
20
76
camping gas
21
73
cheap oil
19
64
expensive oil
19
66
Fuel
Temp
change
in C
Rank
order
Calculate the temperature change of a beaker of water for the
same amount of each fuel. Then decide which fuel is best.
Running an airline
These are the results presented to an airline after a test of
four fuels. Calculate the energy given off per gram of fuel for
each.
Which do you think is the ‘best’ fuel?
Fuel
Temp
before
(C)
Temp
before
(C)
Temp
Energy
difference transferred
(J)
(C)
Mass of
fuel
used (g)
A
20
56
3.2
B
21
64
4.3
C
19
52
3.6
D
20
61
3.9
Energy per
gram (J/g)
New drugs
•
1.
2.
3.
Extracted from plants and other natural products
Crushed to disrupt and break the cell wall to release the desired product
Boil in a suitable solvent to dissolve compound
Chromatography to separate and identify individual compounds
Expensive
research and development time and associated labour
costs;
time required to meet legal requirements including
timescale for testing and human trials;
anticipated demand for new product ;
length of pay back time for initial investment.
TESTING
•
•
•
•
•
•
•
•
•
scientist need: labour/salaries/wages/cost of workers.
electricity/energy/gas/power costs.
Time taken to complete process.
Equipment cost
Health and safety issues with the drug
Pollution controls.
Rent, water rates all cost money.
The question mentions two factors that are both expensive and
TIME consuming.
Learn all of these in case it comes up as a 6 mark question.
6 marks question on drugs
Answers:
NOTE: Scientist publish findings
about new drugs to allow other
scientist to test their findings and
see if they get the same results. To
allow doctors and pharmacists
know about the drug. To show that
their drug is safe.
To give scientist chance to develop
Different forms of the same element in the same physical state.
Properties
Structure
Use
•
•
•
•
•
four strong covalent
bonds
No free electrons
Cutting tools
Jewellery
•
Colourless
transparent
hard
high melting pt
Does not conduct
electricity
Lustrous
•
•
•
•
•
Black, opaque
Soft, slippery
High melting pt
Conducts electricity
Lustrous
layers
layers-weak forces
strong covalent
bonds
delocalised e-
Pencil lead
Lubricants
Electrodes
C60
semiconducto
rs in electronic
circuits
reinforcing
structures
Graphite
Allotrope
Diamond
Allotropes
Buckminster
Fullerene
nanotubes
•strong
• conductors of electricity
•black solid
•deep red when in petrol.