Scholarship

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The Scholarship follows the same syllabus although questions require a much better understanding of the subject.
The questions need to be answered in far more depth with clear, well argued answers based on scientific principles.
A scholarship candidate would need to have studied work outside the requirements of the syllabus.

Writing scholarship essays

Heading

Start with general introduction; often this will be an overview of what the title means.

Summarise the main points of significance

Go into more detail about your significant points, but be precise, factual and objective, do not keep repeating yourself or be too subjective.

Sum up, bringing in your own opinions if relevant.

Examples

1. Water

2. How urban development might effect the surrounding ecosystem

3. The use of plastics in modern life

1.
Water

Water is a colourless, odourless liquid. It has a boiling point of 100C and freezes at 0C.

It is a compound of oxygen and hydrogen and can be reduced by reactive metals like sodium.

Sodium + water ---> sodium oxide + hydrogen

Water makes up 60% of the Earth's surface and 75% of our body volume.

Water has many biological, industrial and domestic uses.

Main uses for water

Industry: The cooling properties of water and its use as a solvent make water valuable in many types of industry. Large amounts of water are used in the manufacture of steel and other materials, mostly as a coolant. This is why large factories are often placed near rivers.

Domestic: Water is used for washing, baths, flushing toilets along with a variety of other household uses.

Pleasure: Water sports like sailing and swimming are a valuable source of recreation.

Biological importance of water

Water is a vital component in organisms for a number of reasons:

Water is a good solvent which makes it a useful medium for chemical reactions to take place in the cells. It also allows chemicals to reach all parts of the cell.
It is used to transport chemicals such as food and waste around the organisms, either as blood in animals or sap in plants.
It is needed for various chemical reactions eg in photosynthesis.

The water in oceans, rivers and lakes makes a valuable home for a large number of organisms. It provides a far safer and stable environment than land based animals have. It supports their body weight, removing the need for bulky skeletons. It protects them from any rapid changes in air temperature. and prevents their bodies from drying out. It provides a large freedom of movement in all directions. Food and gases present in the water can easily be used by those organisms that need them.

Being transparent light can pass through water which allows photosynthesis to take place in the chloroplasts.

Water at 4C has a higher density than water at a lower temperature. This causes ice to float and causes a layer of warmer water at the bottom of a frozen pond, allowing organisms to survive the winter.

The very first life appeared in water, and without water no life would be possible.

2.
How urban development might effect the surrounding ecosystem

The presence of any development can have both long term and short term effects on the ecology of an area.

The initial impact will be the removal of the habitat. Building programs will remove woods and fields, the home of many animals and plants. Ponds will get filled in, and roads can cause dangerous barriers for animals like frogs trying to return to their breeding site.

Farming programs can be significant:

Food chains can be disturbed by removing hedges which are the breeding place for birds and small mammals.

The destruction of animals which are found to be a nuisance such as foxes or insects will also effect established food chains.

Increased use of fertilizers can clog up small streams and ponds with plants.

Pesticides or fungicides can enter a food chain and have long term effects on many other organisms.

Farming and the presence of an increased population could lead to land erosion, Where valuable nutrients are washed from the soil.

The increased industry and population will lead to increased pollution.

For example:

Acid rain caused by sulphur dioxide from factories or nitrogen dioxide from car exhausts. This can damage many forms of wild-life and cause increased erosion of limestone buildings.

Smoke from cars and factories will also make plants and buildings look unsightly.

Noise from increased traffic and factories can be a nuisance.

Litter and other non-biodegradable waste can make ponds and hedges look untidy as well as being a danger to small animals.

Any urban development needs to be carried out with care and appreciation of the harm it could cause.

These would need to be balanced against the economic and social benefits to the people living there.

3.
The use of plastics in modern life

Introduction

Plastics belong to a group of materials called polymers. They have long chain molecules consisting mostly of hydrogen and carbon.

They are mostly formed by the processing and treatment of fractions obtained from crude oil.

Uses

There are many kinds of plastic with a wide range of properties:

eg PVC (polyvinyl chloride)

Polythene

Nylon

Acetate

PTFE (polytetrafluoroethylene)

Acrylic resins (eg Perspex)

Due to the wide range of properties they have an equally wide range of uses:

Fabrics (polyester or nylon shirts)

Kitchen utensils (washing up bowls)

Mouldings:Cases (for calculators, small games etc)

Plastic foam for chairs and soft furnishings

Medical (sutures, artificial cartilage)

Advantages:

Plastics are easily moulded, comparatively cheap and easy to colour during manufacture. This makes them suitable for items like low-cost toys, disposable pens or disposable cups.

They can have a very high strength/weigh ratio, they do not corrode and can be very hard-wearing which gives them may industrial and medical uses (eg low friction bearings and medical implants)

Disadvantages:

Plastics are difficult to dispose of: they are non-biodegradable and often produce toxic fumes or dense black smoke when burnt so they are not very environmentally friendly.

Most plastics in every-day use are not very strong and catch fire easily

The manufacturing process uses up energy and often produces its own pollution.

They are manufactured from oil which is a non-renewable energy source.

Summary

Plastics are a very convenient replacement for wood or metal and plastics can be designed with properties to suit individual needs, but they must be used with discrection and with thought for the future.

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