21c physics | electromagnetic waves | ©stevenage schools network triple science support programme...

21C Physics | Electromagnetic waves |

©Stevenage Schools Network


Triple Science Support Programme

The Stevenage Network of Schools

Starters and Plenaries

June 2008



•Chemistry of the Living world

Welcome!

21st Century Science presents:



Chains and rings

• It is useful to think of organic compounds as a chain of carbon atoms shown below.

•Each carbon atom can make up to 4 bonds each one being covalent.



Hydrocarbons- The Alkanes

•This very important class of compounds is commonly used as fuel eg. Petrol (octane)

In this lesson You will find out about: The alkane series of hydrocarbonsPhysical properties of alkanesChemical Reactions of alkanes



click here to see the crude oil animation

Activity



Stage 2: Alcohols

•Surprisingly alcohols are not just a sure fire way to get smashed.

•They are of great importance to the chemistry world too.•They are very similar to alkanes but include an -OH (hydroxyl)

group on one of the carbons.

In this lesson you will learn about:•Physical properties of alcohols•Chemical properties of alcohols



click here to see the alcohol animation

Activity



Stage 3: Carboxylic Acids

•Carboxylic acids are found in great abundance in food processing as well as fruit. For instance vinegar is made up of the carboxylic acid Ethanoic acid.

In this lesson you will find out about:Structures and properties of organic acidsAcids in vinegar and other foodsCarboxylic acids as weak acids



http://www.zerobio.com/drag_oa/coolermolecules/drag_and_drop_cooler_molecules.swf

Activity



Stage 4: Esters

•Esters are very recognisable by their fruity odours as they are present in apples, bananas and much more.

•They are produced from reactions between alcohols and carboxylic acids.

In this lesson you will understand how:Alcohols and carboxylic acids form estersEsters are synthesised practically



http://downloads.bbc.co.uk/schools/gcsebitesize/science/activity/activity42/activity.swf

Activity



Stage 5: Fats and oils

•Naturally occurring fats and oils are tri-esters, meaning three ester links in one molecule

•You should remember from last lesson that esters are produced through a reaction between alcohols and carboxylic acids

In today's lesson you will investigateStructures of fats and oilsSaturated and unsaturated compounds




Activity



How much? How Fast? How far?

All chemical reactions involve a change in energy because old bonds are broken, and new bonds are formed



Energy changes in chemical reactions

•Reactions can take in energy from their surroundings. These are known as an endothermic reactions.

•Reactions can also give out energy in the form of an exothermic reaction.

In this lesson you will explore:Endothermic and exothermic reactionsEnergy level diagramsBond breaking and formingCalculating energy changes



http://www.bbc.co.uk/schools/gcsebitesize/science/flash/gcsechem_06.swf

Activity



How fast?????

•The activation energy of a reaction is the minimum energy requirement for a reaction to take place.

•The kinetic energy the molecules obtain is incredibly important as it determines whether the activation energy is reached.

In this lesson you will studyCollisions between moleculesActivation energies



http://www.youtube.com/watch?v=VbIaK6PLrRM

Video



Reversible Changes

•Many reactions are reversible processes for instance the melting or freezing of water.

•Chemists have to understand what conditions to allow the reaction to progress as far in one direction as possible. This will create a high yield.

In today’s lesson you will investigate:Reactions that go both waysFactors affecting the direction of change



http://www.bbc.co.uk/schools/gcsebitesize/flash/gcsechem_36.swf

Animation



How far?•Reversible changes that your learnt last lesson exist in a state of balance, or dynamic equilibrium.

•The forward and reverse reactions are constantly occurring, but the rate to which both of them occur determines whether more product or reactants are made.

In this lesson you will find out about:Chemical equilibriumDynamic equilibriumStrong and weak acids



http://www.bbc.co.uk/schools/gcsebitesize/flash/ch03009.swf

Animation



Topic 3: Chemical Analysis

•Analytical measurement of chemical compounds is of great importance to our everyday lives. It ensures things are safe and do not cause any negative effects e.g. shampoo causing an allergic reaction :^o

•Medicines have to go through years of testing before they are even trialled on humans.



Analysis stage 1: Sampling•Analysts work with samples of materials, using as many different samples as possible.

•Large samples like the power rangers in the background are more representative because they produce a more accurate picture or the material as a whole.

This lesson will uncover:The importance of samplingSampling and analysing in the field and the labPower ranger kung-foo moves



Checking up on food colours

Chromatography has many uses:•To separate and identify chemicals in a mixture•Check the purity of a given chemical•Purify small samples of a chemical

This lesson will focus on:Principles of chromatographyPaper chromatographyThin layer chromatography

Chuck Norris says:

Chromatography kicks ass

mikedorazio.wordpress.com/2008/02/29/



Find the forgery:Ash Ketchum style

•Chromatography can be used to analyse colourless compounds for their consistency.

•Chromatographic methods rely on some sort of indication i.e. colour change to confirm the presence of a particular compound

Your task today is to use thin layer chromatography to distinguish between metal ions!

Lets Go bidoof!Lets find the forgery!



Gas Chromatography

•This technique is used to separate complex mixtures more effectively than paper or thin layer chromatography but is very expensive.

•It can not only detect small quantities of compounds but can also measure how much of each compound is present in a sample.

Today’s lesson will cover:Gas chromatography (how surprising!)Retention times



http://www.wooster.edu/Chemistry/analytical/gc/default.html

Interactive



Concentration

•Concentration is the measure of how much of a compound is dissolved per unit of volume.

•Concentration must be calculated very carefully if an accurate piece of research is to be conducted.

In this lesson you will learn:What apparatus is required to make an accurate standard

solution.How to make up a standard solution



Using Pipettes and burettes

•When using exact volumes of solution it is vital to use accurate equipment in an investigation.

•Pipettes and burettes are used greatly in practical chemistry particularly in titrations.

This lesson will cover:The key features of burettes and pipettesHow to correctly use burettes and pipettes



http://uk.youtube.com/watch?v=Y-5QJIr7Xm4

Video



Analysing Vinegar

•Titration is a standard procedure where a solution of known concentration is reacted with an unknown solution to determine its concentration.

Today’s action packed hour includes:Acid-alkali titrations (using vinegar OMG)Standard solutions



http://media.coolschool.ca/player.php?course=chem12&file=lab20c.flv

Titration video



Valid analytical measurement

•True values cannot be found by performing a single experiment.

•Repeats must be carried out to ensure reliability where a mean value is produced.

•Averages can be used to provide a best estimate of the true value.

This lesson will cover:Examination of previous titration resultsEvaluating your work



Synthesis of weed killer

•Herbicides play a pivotal role in the food production industry because to maximise yields, weeds which are “unwanted plants” must be destroyed.

•Herbicides must be chemically synthesised and then purified before they can be sold on the open market.

In happy hour today you will learn:How weedkillers are madeHow the product is separated from the reactantsHow the weedkiller is purified.




Activity



Chemical Industry

One of the many large scale processes in the chemical industry today is the production of nitric acid.

By using ammonia (NH3), water and oxygen along with the use of catalysts and higher pressures nitric acid is produced

Today’s hour includes: Large scale manufacturing of nitric acidFinding more examples of large scale manufacturing



Greener IndustryThe chemical industry is constantly moving forward,

reinventing many of its processes to make them kinder to the environment.

Greener chemistry refers to:•Turning to renewable resources•Creating higher yields•Cutting down use of hazardous chemicals•Improving efficiency•Reducing waste•Preventing pollution



Todays lessons will:Allow you in groups to look at a specific aspect of greener

chemistryReport back in groups with a presentation or hand out about

a specific aspect




Activity



Catalysts•Catalysts provide an alternative reaction pathway which

lowers the activation energy•This means more molecules have sufficient energy to react.Catalysts increase reaction rates but do not change the yield of

the products.

Today’s glorious hour includes:How catalysts workThundercat Sword moves



Three routes to ethanol•You should remember from lesson 25 the principles of green chemistry, for example, turning to renewable sources.

•These principles can be applied to ethanol production.

This lesson will cover the three methods of producing ethanol, which are:Oxidation of hydrocarbonsThe Monsanto processThe Cativa process



Which route is best?

•It is very important to assess the attributes of each method of ethanol production in order to justify which one will have the least damaging effects.

Last chemmy lesson ever involves:Working in groups and using the information you gained

last lesson your task is to decide which method is best for the chemical industry

21c physics | electromagnetic waves | ©stevenage schools network triple science support programme...

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