Topic and Option Changes

Topic and Option Changes New, Used and Reorganized

Topics 1 & 11 Topic 1: Quantitative Chemistry: (11hrs  12.5hrs) Additional aspects include: Solving problems involving the relationship between T,P and V for a fixed mass of ideal gas Ideal gas calculations using pV=nRT Analysis of graphs relating to pV= nRT Topic 11: Measurement and Data Processing New topic (2hrs)

Topics 1 & 11 Continued TOK: • Use of state symbols – when are they necessary in aiding understanding and when are they redundant? • Assigning numbers to masses of elements allowed chemistry to develop into a physical science and use math to express relationships between reactants and products. • Distinction between Celsius and Kelvin scales as an example of an artificial and natural scale could be discussed. Labs: • Volumetric analysis • Determination of empirical formula • Determining molar mass of a gas ICT: • Simulations of gas laws (http://phet.colorado.edu/web-pages/simulations-base.html) • Virtual experiments

Topics 2 & 12 – Atomic Structure Topic 2: (4 hrs) Key additional aspects include • Uses of radioisotopes • The mass spectrometer Topic 12: • (4hrs  3hrs) Key change - Mass spectroscopy moved to topic 2 ***Analysis of fragmentation patterns/determining molecular mass is now only available in Option A

Topic 2 & 12 Continued Aim 8: Usefulness and dangers to living things of radioisotopes TOK: Atomic models and theories – are they accurate descriptions of the natural world or are they useful interpretations for prediction, explanation and control of the natural world? Labs: Observing emission spectra ICT: Simulations for mass spectrometer

Topic 3 & 13: Periodicity Topic 3 (6hrs) No major changes Topic 13: (4hrs) No major changes Aim 8: • Environmental effect of non-metal oxides • Economic significance of catalysts in Contact and Haber process. TOK: • Is the PT a description or explanation of the chemical and physical properties of elements and compounds? • Predictive power of Mendeleev's PT – example of a scientist as a risk taker Labs: • Reactivity of alkali metals • Reactions of halides with halogens ICT: • Databases/spreadsheets/simulations

Topic 4 &14: Bonding Topic 4: (12hrs  12.5hrs) Additional aspects include • Structure and bonding of carbon allotopes • Structure and bonding of Si and SiO2 Topic 14: (6hrs 5hrs) Key change • Structures of carbon allotropes moved to topic 4

Topic 5 & 15: Energetics Topic 5: (11hrs  8hrs)Key changes include • Removal of entropy Topic 15: (4hrs 8hrs) Key change • All entropy and spontaneity aspects now covered in AHL • Removal of spontaneity

Topic 6 & 16: Kinetics Main changes • Core expanded to include Maxwell-Boltzmann distribution theory • Core no longer needs to cover mechanisms or rate determining step • HL has less on: types of catalysis half life definition and calculations no longer specified (but may be implicit from 1st order rate graphs)

Topic 6 & 16: Kinetics Cont. Possible labs • Factors determining rate of reaction (excellent for concepts of variables and controls) • Determination of the order of a reaction from empirical methods • Calculation of activation energy from Arrhenius graph plots ICT Vernier experiments (see list) • http://www.mpcfaculty.net/mark_bishop/KMT.htm For a simulation of the basics of kinetic molecular theory • http://lorax.chem.upenn.edu/Education/MB/MBjava.html The Applet shows a colorful simulation of the relationship between molecular speeds and their distribution. • http://www.cambridgeassessment.org.uk/research/innovationassessmentlearning/enigma/simulations/marble/marble.html • http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/flashfiles/kinetics2/rxnRate01.html for simulations of experiments illustrating the affect of different factors on reaction rates. You can change the variables and see the effect by the graph plots resulting.

Topic 6 & 16: Kinetics Cont. TOK • The balanced equation of the reaction gives no information about its rate. Information is based only on experimental (empirical) data. Consider the relative validity of conclusions based on experimental and on theoretical data. Aim 8 • Role of catalytic converters in vehicles; catalysts including - many heavy metals - in industry • Significance of rate of reaction determinations in atmosphere and oceans • Maxwell and Boltzmann: names linked but two very contrasting characters • Svante Arrhenius: also acid base theories, first proposed link between CO2 and greenhouse effect in 1896

Topic 7 and 17: Equilibrium Main changes • Changes in core are very minor: Le Chatelier’s principle needs to be understood but not stated • Applications of equilibrium theory in industrial processes more open ended • Effectively no changes in AHL Possible labs • Many good demonstrations and simulations – see extensive OCC thread on this • Graphical analysis of boiling points of different liquids • Calculation of Kc in esterification reaction

Topic 7 and 17 Cont. ICT • Vernier experiments (see list) • Use of spread sheets and graphical display to investigate the position of equilibrium • Downloadable Flash files with excellent animations: http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/simDownload/index4.html#abEquiibria TOK • Equilibrium reactions are usually considered as having reached a “steady state’ ; to what extent is this true? • How effectively can we make conclusions about the “how far?” question in isolation from the “how fast?” observation?

Topic 7 and 17 Cont. Aim 8 • Equilibrium theory is a major consideration in determining conditions in many modern industrial processes – with outcomes both positive and negative • Fritz Haber – significance of his work in place and time Syllabus links • Topic 6 / 16 Kinetics: considerations of optimum conditions for industrial processes • Topic 1 Quantitative chemistry: gas properties and changes of state

Topic 8 & 18:Acids and Bases Main changes: Topic 8: • Core has added: Bronsted – Lowry and Lewis theories • Identification of conjugates • Use of pH meter now specified • Core no longer covers: Buffer solutions • Titrations Topic 18: (11hrs  10hrs) • Theories of acids and bases moved to Topic 8 • All buffer solution work now covered here • All acid-base titration work covered here • Buffer theory –expanded to specify calculations of buffer pH

Topic 8 & 18 Cont. Possible labs • Titration curves • Acid or base standardization techniques • Indicator end points; preparation of natural indicators • Effect on pH of acid strength and concentration • Preparation of buffers; effect of temperature, dilution etc. • Calculation of pKa from half neutralization ICT • Vernier experiments (see list) • Downloadable Flash files with excellent animations and virtual labs from iastate • Titration curves used for data logging, databases, spreadsheets and simulations

Topic 8 & 18 Cont. TOK • pH scale is described as an artificial (or an arbitary) scale. To what extent is this true of all scales used for measurement? • Fallacies and misconceptions regarding the pH scale: range, significance of 7 etc. Aim 8 • Acid rain – cultural, ecological and international considerations • Global warming – effect on pH of oceans

Topic 9 & 19: Oxidation and Reduction Main Changes: Topic 9: (7hrs) • Addition of redox equations • Deducing simple half-equation and redox equations • Identifying oxidizing and reducing agents • Redox equations (note word “simple” has been inserted) • Specification of nature of reaction and polarities of electrodes in both voltaic and electrolytic cells • Core has lost: Electroplating • Clarification that reactivity series does not have to be learned Topic 19: (7hrs  5hrs) • Redox equations moved to Topic 9

Topic 9 & 19 Cont. Possible labs • Metal / metal ion displacement reactions • Halogens / halide ion displacement reactions • Constructing voltaic cells and measuring voltage • Electrolysis experiments with different aqueous solutions and electrodes • Electroplating ICT • Vernier experiments (see list) • Downloadable Flash files with excellent animations and virtual labs from iastate TOK • Consider the arbitrary nature of oxidation numbers: does this limit their usefulness?

Topic 9 & 19 Cont. Aim 8 • Historical context of metal extraction and implications • Resource extraction – issues of economy, conservation and control • Mercury poisoning in Japan; other heavy metal pollutants • Battery disposal vs rechargeable types • Fuel cells – real and potential uses Syllabus links • Topic 3 / 13 Periodicity: relative ease of oxidation / reduction of metals and nonmetals • Topic 5 / 15 Energetics: considerations of spontaneity • Option C Industry and technology: fuel cells and rechargeable batteries; electrolysis of alumina

Topic 10 & 20: Organic Chemistry Topic 10 Added: • Free radical substitution mechanism for CH4 and C2H6 with Cl2 and Br2 (p65) Suggested approaches to teaching: • Link to bond energy calculations (evidence for mechanism) • Simulations of mechanisms (many good websites – see handout) • http://www.york.ac.uk/org/seg/salters/chemistry/DIY/a.html • Use of molecular models • LAB: Simple lab demonstrations (test-tubes with hexane/Br2 –place in the dark and in sunlight. • Equations and descriptions of oxidation of primary and secondary alcohols (p66) • Simple test-tube reactions of H+/K2Cr2O7 with primary, secondary and tertiary alcohols • Good way to introduce organic techniques such as distillation/reflux

Topic 10 & 20 Cont. • Nucleophilic substitution reactions of RX with NaOH in terms of SN1 and SN2 mechanisms (p.67) Suggested approaches to teaching: • Simulations of mechanisms • Link this to kinetics/order with HL groups • Use of molecular models • Use of simple test-tube reactions where possible (with AgNO3 added as precipitates of AgX will form of the corresponding halide) • Deduction of reaction pathways (2 step max) p67 Suggested approaches to teaching: • Place in context of industrial importance (eg. Synthesis of drugs) • Synthetic route maps – students can construct their own with a named starting material • Filling in reagents, conditions on a synthetic route map

Topic 20: Organic chemistry (9hrs  10hrs) HL has lost: • Structure determination by mass spec, nmr, IR (now in Option A) • Reactivity of alkanes (now in Topic 10) • Evidence and structure of benzene (now in Topic 14/Option G) • Elimination reactions of alcohols (now in Option G) HL has added: • Factors affecting nucleophilic substitution (eg. Identity of the halogen, primary,secondary, tertiary) • Relative strength of OH- and H2O as nucleophiles • Description and explanation of reactions of primary RX with NH3 and KCN in terms of SN2 mechanism • Reduction of nitriles (RCN to RCH2NH2) using H2 and Ni catalyst • Elimination reaction of HBr from bromoalkanes forming alkenes • Condensation reactions of alcohols and amines with RCOOH including formation of polyesters and polyamides • Stereoisomerism –optical and geometric • Reaction pathways – 2 stage conversions max

Topic 10 & 20 Cont. Teaching approaches: • Introduce the concept of organic chemistry into the course as early as possible (eg. In the bonding topic) • A sound understanding of organic chemistry depends on a good grasp of physical chemistry principles so it makes sense to incorporate the ideas of energy, kinetics and bonding wherever possible. This will develop the student’s understanding of concepts and problem-solving skills. • Give the students time to reflect and become familiar with this topic so teaching it earlier rather than later in the course is recommended. • Linking topics to students own experience of organic chemistry will stimulate their interest • Hands on experience, whether using molecular models, computer simulations, lab activities are essential to the learning process.

Teaching approaches cont.: • Use of simple test-tube reactions where possible (with AgNO3 added as ppts of AgX will form of the corresponding halide) • Use of bond energies and electronegativity differences to predict which RX (where X=Cl,Br or I) will hydrolyse most rapidly • Relationship between experimental evidence and reaction mechanism (linking kinetics topic) • Lab prep of esters/aspirin and their purification • Demo of nylon prep • Optical isomerism - link to known everyday examples of optical isomers (limonene, thalidomide – how some drugs need to be in the form of one pure enantiomer and several leading technology companies (eg. Chiroscience) now specialize in producing pure enantiomers using synthetic routes which only produce this one form) • Extraction of limonene from orange peel (great introduction to organic techniques) and testing of the product for unsaturation etc • Use of model building in all cases • Lab sheet –hands on activity

Topic 10 & 20 Cont. TOK: • Value of different models with different depths of detail • Use of language of chemistry in classifying and distinguishing between structures. • Use of conventions in representing 3D molecules in 2D ICT: • Use of simulations • Use of spreadsheets (calculating the heats of combustion of alcohols) Aim 8: • Consequences of using fossil fuel as main energy source – as so many products can be derived from fossil fuels because of C’s rich chemistry, ‘are they too valuable’ to burn? • Economic importance of alkenes/condensation reactions (polyamides, polyesters)

Option A: Modern analytical chemistry (formerly Option G) A1 Analytical techniques (1hr) • Now , just have to state the reasons for using analytical techniques and state that information from a variety of analytical techniques are needed for determining the structure of a compound A2Principles of spectroscopy (2hrs) • As before except that the operating principles of double –beam IR has been moved to A3 A3 IR spectroscopy (3hrs) • As in the old guide including the operating principles of double-beam IR A4 Mass spectroscopy (2hrs) • Determining M of a compound from M+ peak / analysis of fragmentation patterns to find the structure of a compound (no reference any more to M+1, M+2 peaks etc) A5 NMR (2hrs) • Deducing the structure of a compound given information from its nmr –only need to deduce the # of different H environments and the relative # in each environment. No assessment of interpretation of splitting patterns here) • Use of nmr in body scanners as before.

Option A Cont. NEW: A6 Atomic absorption spectroscopy (3hrs) • New (An overview is give on this RSC website http://www.chemsoc.org/pdf/LearnNet/rsc/AA_txt.pdf) • Used to analyze metals; atomic absorption spectroscopy (AAS) determines the presence of metals in liquid samples. Metals include Fe, Cu, Al, Pb, Ca, Zn, Cd and many more. It also measures the concentrations of metals in the samples. Typical concentrations range in the low mg/L range. • In their elemental form, metals will absorb UV light when they are excited by heat. Each metal has a characteristic wavelength that will be absorbed. The AAS instrument looks for a particular metal by focusing a beam of uv light at a specific wavelength through a flame and into a detector. The sample of interest is aspirated into the flame. If that metal is present in the sample, it will absorb some of the light, thus reducing its intensity. The instrument measures the change in intensity. A computer data system converts the change in intensity into an absorbance. As concentration goes up, absorbance goes up. A calibration curve is constructed by running standards of various concentrations on the AAS and observing the absorbance. A7 Chromatography (2hrs) • Stating the reasons for using chromatography, explanation that all chromatographic techniques involve a stationary and mobile phase and outline the use of paper chromatography, TLC and column chromatography A8 HL Visible and UV spectroscopy (3 hrs) • No major changes

Option A Cont. A9 HLNMR • Explain the use of TMS as reference standard • Analyse 1H NMR spectra in addition to A5, chemical shift and splitting patterns should be interpreted. A10 HL Chromatography • GLC,HPLC chromatography and deduction of most appropriate technique for separating the components in a mixture. as in option G. Aim 8: • Protons in water molecules in human cells can be detected by MRI giving a 3D view of organs in the human body. • Application of UV-Vis spectroscopy in suncreams Aim 7: • Simulations of spectroscopic techniques • Use of data banks

Option B: Human Biochemistry Main changes • Removes consideration of components of diet • Increased content on polysaccharides including dietary fiber • ‘Fats’ replaced by ‘Lipids’ reflecting broader content including omega unsaturated fatty acids and cholesterol • Expansion and renaming of ‘Vitamins’ to include other micronutrients and macronutrients • Removal of ‘Metal ions’ but incorporation of some of this into ‘Respiration’ • Addition of ‘Respiration’, including aerobic and anaerobic pathways Possible labs • Chromatography and electrophoresis of amino acids • Gel electrophoresis of DNA • Enzyme experiments – effect of temperature and pH on activity • Ethanol and CO2 production from yeast

Option B Cont. ICT • Vernier data logging • Simulations of DNA profiling TOK • Is there a difference in the way that biologists and chemists view molecular structures, for example of proteins? • Who owns the knowledge often described as ‘the secret of life’ – the genetic code? Aim 8 • Ethical considerations of data bases of genetic information • Increasing global concern about medical conditions related to dietary choices – obesity, diabetes etc. Syllabus links • Topic 5/15 Energetics: determining enthalpy values • Topic 10 / 20 Organic: polymerization reactions • Topic 9 / 19 Oxidation and reduction: redox reactions in respiration • Topic 6 /16 Kinetics: enzymes as catalysts • Topic 8 /18 Acids and bases: ionization of acid and amine groups, isoelectric point

Option D: Medicines and Drugs Main changes • LD50 no longer included • Therapeutic window now included • Broad and narrow spectrum of antibiotics no longer included • Combinatorial chemistry expanded to include other aspects of ‘Drug design’ • Anesthetics removed Possible labs • Aspirin synthesis • Antibiotic plates – zones of inhibition of growth • Oxidation of ethanol – breathalyzer reaction ICT • Vernier data logging • Data banks for health records, drug reactions etc.

Option D Cont. TOK • Different analgesics differ in how they help reduce pain – either at source, or in the perception. Is either of these methods intrinsically more ‘real’ as a pain killer? • To what extent does knowledge about drug effects limit or contribute to their usage? • Consider the suggestion that the simplest life form (virus) is the one to which we are the most vulnerable. Aim 8 • Ethical considerations of the pharmaceutical industry and distribution of drugs • Ethical issues of drug testing – on animals and humans • Global distributions of diseases Syllabus links • Topic 8 /18 Acids and bases: neutralization reactions – antacids • Topic 10 / 20 Organic: optical isomers, functional group identities and properties

Option E: Environmental Chemistry Main changes • Acid rain expanded to include forms of dry precipitation • Removal of influence of particulates from greenhouse effect • Removal of most of ‘Water suitable for drinking’ • Removal of ‘Toxic substances in water’ • Addition of Soil • Addition of Waste • Addition of Water and Soil Possible labs • Acid rain synthesis • Sewage treatment visit • Fresh water from sea water – multi stage distillation / reverse osmosis • Demonstrations of measurement of radioactivity • Measurements of soil pH and ion testing

Option E Cont. ICT • Vernier data logging • Use of models in mapping and predicting climate change TOK • What confidence do we have in the data on climate change? What would constitute more compelling knowledge in this field? Aim 8 • Consider the importance of long term planning by governments to address environmental issues • Discuss the responsibility of the individual vs governments in confronting environmental issues • What are the implications of the developing global economy for environmental degradation? What moral rights do we have in this regard?

Option F: Food Chemistry New Topic

Option G: Further Organic Chemistry Option G has lost: • Stereoisomerism • Free radical substitution • Elimination of HBr from bromoalkanes Option G has added for SL: • Organometallic compounds – Grignard reagents • Francois Grignard (1871-1935) realized the synthetic potential of organometallic compounds. • Ionic character of the metal-carbon bond where C unusually carries the partial negative charge • Important way of extending the carbon chain and generally in synthetic routes Prepared as follows: C2H5I + Mg  C2H5MgI (prepared in dry ether as the Grignard reagents hydrolyse in water) • Grignards can be reacted with CO2 (to produce carboxylic acids) and with aldehydes and ketones to produce secondary and tertiary alcohols. • Occur by nucleophilic addition • Evidence for structure of benzene from chemical and physical properties. Option G has added for HL: • Addition –Elimination reactions (HL) • Reactions of acid-anhydrides/ acyl chlorides with water, alcohols, ammonia and amines (and addition-elimination mechanisms of acyl chlorides)

Option G Cont. Approaches to teaching: • Lab preparation of aspirin from ethanoic anhydride and salicylic acid • Subsequent purification/analysis of aspirin Some useful websites to support teaching of organic chemistry: • http://www.colby.edu/chemistry/OChem/demoindex.html#table Great animations of organic mechanisms (there is also a nice interactive mass spectrometer animation) • http://www.york.ac.uk/org/seg/salters/chemistry/DIY/a.html Salter’s chemistry – this website has examples of application of chemistry. There are also some very clear animations of reaction mechanisms • http://scholar.hw.ac.uk/site/chemistry/topic4.asp?outline=no Great animations relating to stereoisomerism • http://nobelprize.org/nobel_prizes/chemistry/laureates/2001/illpres/game.html Optical isomerism – the chirality game (interactive activity) • http://www.creative-chemistry.org.uk/alevel/module3/index.htm#sheets Useful organic activities and some good labs • http://cwx.prenhall.com/petrucci/medialib/media_portfolio/27.html Organic chemistry movie clips/images • http://www.chemsoc.org/PDF/LearnNet/rsc/Aspirin_full.pdf A very useful resource from the Royal Society of chemistry about aspirin – this includes the history, labs etc • http://www.chem.uic.edu/web1/OCOL-II/WIN/STRUCT/F13.HTM • http://www.chemguide.co.uk/mechmenu.html Good notes on organic chemistry mechanisms • http://www.rod.beavon.clara.net/chemistry_contents.htm Much useful information here on organic chemistry (and other topics)

Topic and Option Changes