Nitrogen reacting with oxygen to form Nitrogen monoxide

1
Combustion (burning) reaction Some chemicals can
react rapidly with oxygen to release energy and
possible light.
Name Health Effects
Sulfur Dioxide Acid rain
Carbon Monoxide A poisonous gas. It reacts with blood and can kill you.
Nitrogen Dioxide Acid rain.Causes breathing problems.Can make asthma worse.
Particulates (tiny bits of solid carbon suspended in the air) Make things dirty.Breathed into your lungs.Can make asthma worse.Can make lung infections worse.
What influences Air Quality? 1. Emissions 
Vehicles release pollutants into the air. 2.
Weather Winds mix up and transport pollutants.

• Incomplete combustion
• If there isnt enough oxygen to the burn the
  fuel completely, incomplete combustion takes
  place.
• Carbon monoxide is formed.
• It also releases small particles of carbon into
  the air.

C1

• Car engines use catalytic converters to reduce
  the amount of pollution released.How it works
• Molecules of polluting gases are pumped from the
  engine past the catalyst.
• The catalyst splits up the molecules into their
  atoms.
• The atoms then recombine into molecules of
  relatively harmless substances such as carbon
  dioxide, nitrogen, and water, which blow out
  safely through the exhaust.

Carbon reacting with oxygen to form carbon
monoxide

• The Earths atmosphere provides a protective
  blanket that supports life.
• Human activities have altered the balance of
  these chemicals as it can be damaged easily.
• The concentration of C02 doubled since the
  burning of fossil fuels.

• Conservation of atomsReactants    ?   Products
• The products have different properties from the
  reactants.
• As a chemical reaction takes place, atoms in the
  reactants are rearranged to make the products.
• No atoms are added or taken away.

Hydrogen reacting with oxygen to form water
A primary pollutant is an air pollutant emitted
directly from a source. A secondary pollutant is
not directly emitted, but forms when other
pollutants (primary) react in the
atmosphere. Example N0 joins with oxygen atoms
in the air to form N02.
Nitrogen reacting with oxygen to form Nitrogen
monoxide
2
Polymer with no cross-links

• What are Polymers?
• A polymer is a long-chained molecule that is
  composed of individual units of ethene, called
  monomers.
• Materials can be obtained or made from living
  things and chemicals. These are known as natural
  and synthetic materials.

The shape and size of the long-chain molecules in
a fibre make the material what it is and gives it
its special properties.
Modifying polymers Different polymers have
different properties, depending on the small
molecules they were made from but the properties
of a polymer can also be changed.
Polymer chains

• Many polymers, such as polythene, contain long
  molecules that lie side by side. These can uncoil
  and slide past each other, making the material
  flexible.
• Long polymer chains have stronger forces of
  attraction than shorter ones. By making the
  chains of a polymer longer, a stronger and less
  flexible material is produced.

Ethene makes polythene
By polymerising other small molecules, a wide
variety of different polymers can be made. These
synthetic materials have many uses.
C2
A Life Cycle Assessment, or LCA, is a study of
the stages in the life of a manufactured product.
It can be used to assess the environmental impact
of the manufacture and use of different materials
and products.

• Getting the right material
• The products that we use are made of different
  materials. Choosing the right material for each
  job depends on the properties of that material.
• Manufacturers and designers have to choose the
  right materials to make their products. They
  decide which materials to use based on their
  properties and cost.

The raw materials for making the product The
energy used to manufacture it
CRADLE
The energy needed to use it The energy needed to
maintain it The chemicals needed to maintain it
USE

• Solid materials can differ in the following ways
• Melting point
• Strength in tension (when pulled)
• Strength in compression (when pushed)
• Stiffness
• Hardness
• Density

Nylon is used to make tights due to its
flexibility.
The raw materials for making the product The
energy used to manufacture it
GRAVE
3
Polymer with cross-links

• Plasticizers
• Plasticizer molecules behave like molecular
  lubricants.
• They push the polymer molecules slightly further
  apart.
• This weakens the intermolecular forces between
  them and allows the polymers chains to slide over
  each other more easily, making the material
  softer and more flexible.
• Unplasticized PVC, usually called uPVC, is hard.
• Plasticised PVC is soft.

• What is Vulcanisation?
• Natural rubber is sticky, deforms easily when
  warm, and is brittle when cold. In this state it
  cannot be used to make products with a good level
  of elasticity.
• Vulcanisation is the process in which rubber is
  heated at high temperatures with sulphur.
• The sulphur forms chemical bonds, or cross-links,
  which link together the chains of individual
  polymers.
• These cross-links lock the material in a regular
  shape and make the material tougher and less
  flexible, increasing its worth and uses.

Sulphur

• Various amounts of crystallinity
• By carefully controlling the amount of branching,
  it is possible to make polymers with various
  amounts of crystallinity.
• This means it is possible to make a polymer with
  the exact properties that are required for a
  particular purpose.

PVC Molecules
C3

• Side Branches
• When polythene molecules made from ethene are
  exposed to pressure, side branches are given off.
• The polymers will still grow but from multiple
  branches and will not line up neatly.
• LDPE in an example of this.

No side branches
Has side branches

• High-Density Polythene (HDPE)
• The polymer molecules line up regularly to give a
  crystalline structure.
• This means that
• The material has a higher density than LDPE.
• The forces of attraction between polymer
  molecules are strong.
• The material is stronger and has a higher melting
  point than LDPE.

• Low-Density Polythene (LDPE)
• The side branches stop the polymer molecules from
  lining up regularly. Its structure is not
  crystalline.
• This means that
• The material has a lower density than HDPE.
• The forces of attraction between polymer
  molecules are weakened.
• The material is less strong and has a lower
  melting point than HDPE.

4

• Food Additives
• Colourings Replace or add natural colours.
• Flavourings Gives the food a certain taste
• Sweeteners Increase sweetness and replaces sugar
  in products using artificial sweeteners such as
  aspartame.
• Emulsifiers Help to mix together substances
  which do not easily mix, such as oil and water.
• Stabilisers Stops these substances separating
  again after they have been mixed.
• Preservatives Prevents growth of microbes such
  as bacteria in foods during storage to increase
  shelf life.
• Antioxidants Prevents reaction of chemicals in
  food with oxygen in the air.

• E Numbers
• A food additive that has passed safety tests to
  allow its legal use in the EU is given an E
  number.
• E100 series Colours
• E200 series Preservatives
• E300 series Antioxidants
• E400 series Emulsifiers, stabilisers and other
  additives

• Carbohydrates and proteins
• Many of the chemicals in living things are
  natural polymers.
• Animals and plants need natural polymers like
  proteins and carbohydrates.
• Food contains natural polymers which are broken
  down during digestion into soluble compounds.
• These are absorbed into the blood and transported
  around the body.
• The breakdown products are then used by the body
  to make new polymers, during a process called
  Synthesis.

Protein Amino Acid Molecule
Carbohydrate Sugar Molecule

• Diabetes is a condition where the amount of
  glucose in your blood is too high because the
  body cannot use it properly.
• Insulin is the hormone produced by the pancreas
  that allows glucose to enter the bodys cells,
  where it is used as fuel for energy.
• Glucose comes from digesting carbohydrate and is
  also produced by the liver.

C3
Plants make their own food through
photosynthesis. They require hydrogen, carbon,
oxygen, NPK and water for growth.

• Intensive farming involves using loads of
  artificial fertilisers, herbicides and pesticides
  and means growing just one crop year after year.
• Organic farming aims to produce crops without
  using artificial fertilisers.

Type 1 Diabetes Type 2 Diabetes
Who it affects Children and teenagers adults under the age of 40 Adults, or over 40s greater risk of those who have poor diets and/or are overweight
How it works The pancreas stops making enough insulin The body no longer responds to its insulin
How it is controlled Injections of insulin for life and a healthy diet Exercise and appropriate diet

• Natural Cycle of Nutrients
• As plants grow they remove NPK from the soil and
  it becomes less fertile.
• Farmers need to be able to replace elements that
  are removed by plants and stop weeds, pests and
  disease.
• These elements are returned to the soil when
  living organisms die and decay, or when animals
  eat other living things.
• These processes means that there is a continuous
  cycling of elements.

• High Blood Glucose Level
• Pancreas produces insulin which enters the blood.
  Insulin allows the glucose to be absorbed by body
  cells, reducing blood glucose.
• Low Blood Glucose Level
• Pancreas stops producing insulin. This results in
  less glucose being absorbed by the body cells and
  more to accumulate in your blood.