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OverviewEdit

C1 Part 2 considers uses of crude oil other than as fuels.

C1.5 Other useful substances from crude oilEdit

Fractions from the distillation of crude oil can be broken down (cracked) to make smaller molecules including unsaturated hydrocarbons such as ethene. Unsaturated hydrocarbons can be used to make polymers and ethene can be used to make ethanol. Ethanol can also be made by fermentation.

C1.6 Plant oils and their usesEdit

Many plants produce useful oils that can be converted into consumer products including processed foods. Emulsions can be made and have a number of uses. Vegetable oils can be hardened to make margarine. Biodiesel fuel can be produced from vegetable oils.

C1.7 Changes in the Earth and its atmosphereEdit

The Earth and its atmosphere provide everything we need. The Earth has a layered structure. The surface of the Earth and its atmosphere have changed since the Earth was formed and are still changing. The atmosphere has been much the same for the last 200 million years and provides the conditions needed for life on Earth. Recently human activities have resulted in further changes in the atmosphere. There is more than one theory about how life was formed.

Lesson SummariesEdit

Specification Reference Summary of Specification contents. Learning Outcomes

C1.5.1 Obtaining useful substances from crude oilEdit

C1 Lesson 28 Cracking HydrocarbonsEdit

a Hydrocarbons can be broken down (cracked) to produce smaller, more useful molecules. This process involves heating the hydrocarbons to vaporise them. Recall that heating large alkanes with a catalyst or steam and hot temperature decomposes to make the hydrocarbon smaller molecules.
The vapours are either passed over a hot catalyst or mixed with steam and heated to a very high temperature so that thermal decomposition reactions then occur.
b The products of cracking include alkanes and unsaturated hydrocarbons called alkenes. Know that some of these smaller molecules are called alkenes.

C1 Lesson 29 AlkenesEdit

b Alkenes have the general formula CnH2n . Recognise alkenes from their structural or molecular formulae.
Know that ‘=’ represents a double bond in the structure.
c&d Alkenes react with bromine water, turning it from orange to colourless. Know that cracking produces more useful molecules including alkenes and fuels.
e Some of the products of cracking are useful as fuels. Know that the presence of double bonds in a molecule can be tested for by the decolorisation of bromine water.

C1.5.2 PolymersEdit

C1 Lesson 30 PolymerisationEdit

a Alkenes can be used to make polymers such as poly(ethene) and poly(propene). In these reactions, many small molecules (monomers) join together to form very large molecules (polymers) Represent polymerisation of ethene using the structural formulae of the monomers and repeated units.

C1 Lesson 31 Uses of PolymersEdit

b Polymers have many useful applications and new uses are being developed, for example: new packaging materials, waterproof coatings for fabrics, dental polymers, wound dressings, hydrogels, smart materials (including shape memory polymers) Know that we use a wide range of polymers developed for specific purposes.
c Many polymers are not biodegradable: so they are not broken down by microbes and this can lead to problems with waste disposal. Identify from properties relevant uses for a polymer.
d Plastic bags are being made from polymers and cornstarch so that they break down more easily. Biodegradable plastics made from cornstarch have been developed. Realise that polymers are often hard to dispose of, and that biodegradable ones offer some solutions to these problems.

No direct Spec Ref.Edit

C1 Lesson 32 Crude oil as a limited resourceEdit

Be aware that crude oil is used to produce fuels and chemicals, and that it is a limited resource.
Evaluate information about the ways in which crude oil and its products are used.

1.5.3 EthanolEdit

C1 Lesson 33 Production of EthanolEdit

a Ethanol can be produced by reacting ethene with steam in the presence of a catalyst. Know that ethanol can be made from ethane and steam, or by yeast.
b Ethanol can also be produced by fermentation with yeast, using renewable resources. Compare the environmental impact of producing ethanol from renewable and non-renewable sources.

C1.6.1 Vegetable oilsEdit

C1 Lesson 34 Vegetable oilsEdit

a Some fruits, seeds and nuts are rich in oils that can be extracted. The plant material is crushed and the oil removed by pressing or in some cases by distillation. Water and other impurities are removed. Know two ways in which vegetable oils are obtained.
b Vegetable oils are important foods and fuels as they provide a lot of energy. They also provide us with nutrients.
c Vegetable oils have higher boiling points than water and so can be used to cook foods at higher temperatures than by boiling. This produces quicker Know that cooking in vegetable oils allows food to be heated to higher temperatures causing different chemical changes to those brought about by boiling in water.

C1.6.2 EmulsionsEdit

C1 Lesson 34 EmulsionsEdit

a Oils do not dissolve in water. They can be used to produce emulsions. Emulsions are thicker than oil or water and have many uses that depend on their special properties. They provide better texture, coating ability and appearance, for example in salad dressings, ice creams, cosmetics and paints. Know how emulsifying agents can help oil and water mixtures to remain mixed.
b HT only Emulsifiers have hydrophilic and hydrophobic properties Give two uses of emulsions.
Identify anomalous results, and calculate a mean from them
Plot a graph or bar chart appropriate to the data collected.
Draw a simple representation of a molecule with hydrophobic and hydrophilic ends.

C1.6.3 Saturated and unsaturated oilsEdit

C1 Lesson 35 Saturated and Unsaturated FatEdit

a Vegetable oils that are unsaturated contain double carbon–carbon bonds. These can be detected by reacting with bromine water.
b HT only: Vegetable oils that are unsaturated can be hardened by reacting them with hydrogen in the presence of a nickel catalyst at about 60°C. Hydrogen adds to the carbon–carbon double bonds. The hydrogenated oils have higher melting points so they are solids at room temperature, making them useful as spreads and in cakes and pastries.

C1.7.1 The Earth’s crustEdit

C1 Lesson 36 Tectonic TheoryEdit

a The Earth consists of a core, mantle and crust, and is surrounded by the atmosphere. Know the three parts of the Earth, and the atmosphere.
b The Earth’s crust and the upper part of the mantle are cracked into a number of large pieces (tectonic plates). Know that all our resources come for the crust, the seas, or the air.
Know key features of Wegener’s theory, and evidence to support it.
Explain why no one believed the theory at first.

C1 Lesson 37 Plate BoundariesEdit

c Convection currents within the Earth’s mantle driven by heat released by natural radioactive processes cause the plates to move at relative speeds of a few centimetres per year. Know that convection currents driven by the heat from radioactive processes cause the movement of the plates.
d The movements can be sudden and disastrous. Earthquakes and/or volcanic eruptions occur at the boundaries between tectonic plates. Explain what earthquakes are and why we cannot predict them
Explain what volcanoes are and why we cannot predict their eruptions.

C1.7.2 The Earth’s atmosphereEdit

C1 Lesson 38 The Earth's AtmosphereEdit

a For 200 million years, the proportions of different gases in the atmosphere have been much the same as they are today: about four-fifths (80%) nitrogen, about one-fifth (20%) oxygen and small proportions of various other gases including carbon dioxide, water vapour and noble gases. Describe the atmosphere today.
l HT only: Air is a mixture of gases with different boiling points and can be fractionally distilled to provide a source of raw materials used in a variety of industrial processes. HT only: Describe how we obtain pure gases from the mixture we call air.

C1 Lesson 39 Evolution of the Earth's AtmosphereEdit

b During the first billion years of the Earth’s existence there was intense volcanic activity. This activity released the gases that formed the early atmosphere and water vapour that condensed to form the oceans. Know that: our atmosphere originated from volcanic gases water vapour condenses to make the seas simple organisms evolved producing oxygen by photosynthesis plants and animals evolved later there is evidence for amounts of oxygen in the air at different times.
c There are several theories about how the atmosphere was formed.
d One theory suggests that during this period the Earth’s atmosphere was mainly carbon dioxide and there would have been little or no oxygen gas (like the atmospheres of Mars and Venus today). There may also have been water vapour and small proportions of methane and ammonia.
f Plants and algae produced the oxygen that is now in the atmosphere.
d There are many theories as to how life was formed billions of years ago.
e HT only: One theory involves the interaction between hydrocarbons, ammonia and lightning.

C1 Lesson 40 Rising Carbon Dioxide levelsEdit

g Most of the carbon from the carbon dioxide in the air gradually became locked up in sedimentary rocks as carbonates and fossil fuels. Describe how carbon cycles round the earth and atmosphere.
h The oceans also act as a reservoir for carbon dioxide but increased amount of carbon dioxide absorbed by the oceans has an impact on the marine environment. Nowadays the release of carbon dioxide by burning fossil fuels increases the level of carbon dioxide in the atmosphere. Describe how human activity has affected the proportions in each part of the cycle.

Summary of C1.5, C1.6, C1.7Edit

C1 Lesson 41 Summary of C1.5, C1.6, C1.7Edit

Summary of Summary of C1.5, C1.6, C1.7