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href="../17867/relating-topics-4-14-to-all-the-other-topics-1.html">Relating Topics 4 & 14 to all the other topics</a></li><li><a href="../17868/example-of-connections-1.html">Example of connections</a></li><li><a href="../34404/hydroxychloroquine-ib-chemistry-1.html">Hydroxychloroquine & IB Chemistry</a></li><li><a href="../35418/ammonium-nitrate-ib-chemistry-1.html">Ammonium nitrate & IB Chemistry</a></li></ul></li><li><a href="../16685/multiple-choice-tests-for-each-topic-1.html" class="father">Multiple choice tests for each topic</a><ul class="level-2"><li><a href="../16687/sl-questions-by-topic-1.html">SL Questions by topic</a></li><li><a href="../16688/hl-questions-by-topic-1.html">HL Questions by topic</a></li></ul></li></ul></li><li><a href="../19044/options--1.html">Options </a><ul class="level-1"><li><a href="../19503/option-a--1.html" class="father">Option A </a><ul class="level-2"><li><a href="../19504/introduction-to-materials-science--1.html">Introduction to materials 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href="../19287/proteins-enzymes--1.html">Proteins & enzymes </a></li><li><a href="../19291/lipids-1.html">Lipids</a></li><li><a href="../19299/carbohydrates--1.html">Carbohydrates </a></li><li><a href="../19305/vitamins--1.html">Vitamins </a></li><li><a href="../19313/biochemistry-the-environment--1.html">Biochemistry & the environment </a></li><li><a href="../19336/proteins-enzymes-ahl--1.html">Proteins & enzymes (AHL) </a></li><li><a href="../19347/nucleic-acids--1.html">Nucleic acids </a></li><li><a href="../19361/biological-pigments--1.html">Biological pigments </a></li><li><a href="../19366/stereochemistry-in-biomolecules-1.html">Stereochemistry in biomolecules</a></li></ul></li><li><a href="../19390/option-c--1.html" class="father">Option C </a><ul class="level-2"><li><a href="../19391/energy-sources-1.html">Energy sources</a></li><li><a href="../19407/fossil-fuels-1.html">Fossil fuels</a></li><li><a href="../19411/nuclear-fusion-nuclear-fission-reactions-1.html">Nuclear fusion & nuclear fission reactions</a></li><li><a href="../19429/solar-energy-1.html">Solar energy</a></li><li><a href="../19437/environmental-impact-global-warming-1.html">Environmental impact - global warming</a></li><li><a href="../19453/electrochemistry-rechargeable-batteries-fuel-cells-1.html">Electrochemistry, rechargeable batteries & fuel cells</a></li><li><a href="../19458/nuclear-fusion-fission-hl--1.html">Nuclear fusion & fission (HL) </a></li><li><a href="../19470/photovoltaic-cells-and-dsscs-1.html">Photovoltaic cells and DSSCs</a></li></ul></li><li><a href="../19078/option-d-1.html" class="father">Option D</a><ul class="level-2"><li><a href="../19079/pharmaceutical-products-drug-action--1.html">Pharmaceutical products & drug action </a></li><li><a href="../19158/aspirin-penicillin--1.html">Aspirin & penicillin </a></li><li><a href="../19174/opiates-1.html">Opiates</a></li><li><a href="../19184/ph-regulation-of-the-stomach-1.html">pH regulation of the stomach</a></li><li><a href="../19194/antiviral-medications--1.html">Antiviral medications </a></li><li><a href="../19211/environmental-impact-of-some-medications-1.html">Environmental impact of some medications</a></li><li><a href="../19254/taxol-a-chiral-auxiliary-case-study-1.html">Taxol - a chiral auxiliary case study</a></li><li><a href="../19258/nuclear-medicine--1.html">Nuclear medicine </a></li><li><a href="../19273/drug-detection-analysis--1.html">Drug detection & analysis </a></li></ul></li></ul></li><li><a href="../16592/practical-scheme-of-work-ia--1.html">Practical scheme of work & IA </a><ul class="level-1"><li><a href="../16682/internal-assessment-1.html" class="father">Internal Assessment</a><ul class="level-2"><li><a href="../18892/scaffolding-the-investigation-1.html">'Scaffolding' the investigation</a></li><li><a href="../18896/timing-organisation--1.html">Timing & organisation </a></li><li><a href="../18905/choosing-the-research-question-1.html">Choosing the research question</a></li><li><a href="../18946/personal-engagement-1.html">Personal engagement</a></li><li><a href="../18950/exploration-1.html">Exploration</a></li><li><a href="../18957/analysis-1.html">Analysis</a></li><li><a href="../18965/evaluation-1.html">Evaluation</a></li><li><a href="../18966/communication-1.html">Communication</a></li><li><a href="../19882/internal-standardization-of-the-ia-1.html">Internal standardization of the IA</a></li><li><a href="../19901/submitting-the-samples-for-moderation-2.html">Submitting the samples for moderation</a></li><li><a href="../33754/ten-suggestions-for-ias-using-secondary-data-1.html">Ten suggestions for IAs using secondary data</a></li><li><a href="../37544/gaining-full-marks-for-a-databased-ia--1.html">Gaining full marks for a databased IA </a></li><li><a href="../19506/ia-example-marking-exercise--1.html">IA example & marking exercise </a></li><li><a href="../23929/genuine-examples-of-moderated-ia-reports-1.html">Genuine examples of moderated IA reports</a></li><li><a href="../25234/examples-of-teacher-marked-ia-reports--1.html">Examples of teacher-marked IA reports </a></li><li><a href="../37542/history-of-internal-assessment-1.html">History of Internal Assessment</a></li></ul></li><li><a href="../16598/mandatory-laboratory-components-1.html" class="father">Mandatory laboratory components</a><ul class="level-2"><li><a href="../16613/formula-of-magnesium-oxide--1.html">Formula of magnesium oxide </a></li><li><a href="../16612/determining-the-mr-of-an-unknown-gas-1.html">Determining the <i>M</i><sub>r</sub> of an unknown gas</a></li><li><a href="../16615/acid-base-titrations--1.html">Acid-base titrations </a></li><li><a href="../16616/a-green-acid-base-practical-1.html">A green acid-base practical</a></li><li><a href="../16617/analysis-of-aspirin-tablets-1.html">Analysis of aspirin tablets</a></li><li><a href="../16618/caco3-in-egg-shells-1.html">CaCO<sub>3</sub> in egg shells</a></li><li><a href="../16644/enthalpy-changes-1.html">Enthalpy changes</a></li><li><a href="../16631/reaction-rates-1.html">Reaction rates</a></li><li><a href="../16635/rate-dependent-factors-1.html">Rate-dependent factors</a></li><li><a href="../16636/determining-ea-for-a-reaction-1.html">Determining <i>E</i><sub>a</sub> for a reaction</a></li><li><a href="../16637/iodination-of-propanone-1.html">Iodination of propanone</a></li><li><a href="../18144/titrations-with-a-ph-meter-1.html">Titrations with a pH meter</a></li><li><a href="../18355/redox-titration-with-kmno4--1.html">Redox titration with KMnO<sub>4</sub> </a></li><li><a href="../16640/voltaic-cells-1.html">Voltaic cells</a></li><li><a href="../16659/3-d-molecular-modelling--1.html">3-D molecular modelling </a></li></ul></li><li><a href="../17168/other-good-practicals-1.html" class="father">Other good practicals</a><ul class="level-2"><li><a href="../17196/common-chemical-reactions-1.html">Common chemical reactions</a></li><li><a href="../227/elements-oxides-of-the-third-period--1.html">Elements & oxides of the third period </a></li><li><a href="../17239/the-halogens-1.html">The halogens</a></li><li><a href="../17162/boiling-points-of-mixtures-1.html">Boiling points of mixtures</a></li><li><a href="../17170/polarity-of-molecules-1.html">Polarity of molecules</a></li><li><a href="../18083/le-chateliers-principle--1.html">Le Chatelier's principle </a></li><li><a href="../19582/determining-kc-for-an-esterification-reaction-1.html">Determining <i>K</i><sub>c</sub> for an esterification reaction</a></li><li><a href="../18164/redox-reactions-of-vanadium--1.html">Redox reactions of vanadium </a></li><li><a href="../18351/chlorine-in-swimming-pools--1.html">Chlorine in swimming pools </a></li><li><a href="../18178/analysis-of-cuii-ions-in-solution--1.html">Analysis of Cu(II) ions in solution </a></li><li><a href="../18179/percentage-of-copper-in-brass-1.html">Percentage of copper in brass</a></li><li><a href="../18356/electrolytic-cells--1.html">Electrolytic cells </a></li><li><a href="../18598/reactions-of-organic-compounds-1.html">Reactions of organic compounds</a></li><li><a href="../18752/hydrolysis-of-halogenoalkanes-1.html">Hydrolysis of halogenoalkanes</a></li><li><a href="../18784/preparation-of-13-dinitrobenzene--1.html">Preparation of 1,3-dinitrobenzene </a></li><li><a href="../19022/determination-of-an-organic-structure-1.html">Determination of an organic structure</a></li><li><a href="../19887/preparation-of-nylon-66-1.html">Preparation of nylon 6,6</a></li><li><a href="../19343/determination-of-vitamin-c-content--1.html">Determination of vitamin C content </a></li><li><a href="../19342/hydrolysis-of-starch--1.html">Hydrolysis of starch </a></li><li><a href="../19159/preparation-purification-of-aspirin--1.html">Preparation & purification of aspirin </a></li></ul></li><li><a href="../18851/ict-in-practical-work-1.html" class="father">ICT in practical work</a><ul class="level-2"><li><a href="../18852/data-logging--1.html">Data logging </a></li><li><a href="../18853/software-for-graph-plotting--1.html">Software for graph plotting </a></li><li><a href="../18854/spreadsheets-for-data-processing--1.html">Spreadsheets for data processing </a></li><li><a href="../18855/databases-1.html">Databases</a></li><li><a href="../18856/computer-modelling-simulations--1.html">Computer modelling & simulations </a></li></ul></li><li><a href="../16594/group-4-project-1.html" class="father">Group 4 Project</a><ul class="level-2"><li><a href="../16595/practicalities-1.html">Practicalities</a></li><li><a href="../16596/reflective-statement--2.html">Reflective statement </a></li></ul></li><li><a href="../16666/a-new-laboratory-1.html">A new laboratory?</a></li></ul></li><li><a href="../16284/exams-1.html">Exams</a><ul class="level-1"><li><a href="../16286/essential-facts-1.html" class="father">Essential Facts</a><ul class="level-2"><li><a href="../16287/objectives-command-terms-1.html">Objectives & command terms</a></li><li><a href="../16288/grade-descriptors-1.html">Grade descriptors</a></li><li><a href="../16289/grade-boundaries-1.html">Grade boundaries</a></li></ul></li><li><a href="../16302/paper-1-multiple-choice-1.html" class="father">Paper 1 (Multiple Choice)</a><ul class="level-2"><li><a href="../16303/advice-to-students-paper-1-1.html">Advice to students (Paper 1)</a></li><li><a href="../31515/practice-paper-1-exams-1.html">Practice Paper 1 exams</a></li></ul></li><li><a href="../16305/paper-2-1.html" class="father">Paper 2</a><ul class="level-2"><li><a href="../16306/advice-to-students-paper-2-1.html">Advice to students (Paper 2)</a></li><li><a href="../16307/areas-of-difficulty-1.html">Areas of difficulty</a></li></ul></li><li><a href="../16313/paper-3--1.html" class="father">Paper 3 </a><ul class="level-2"><li><a href="../16314/advice-to-students-paper-3-1.html">Advice to students (Paper 3)</a></li><li><a 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Chemistry?</a></li><li><a href="../3505/a-modern-paradigm-1.html">A modern paradigm</a></li></ul></li></ul></li><li><a href="../17783/fast-track-to-tests-questions-1.html">Fast track to tests & questions</a><ul class="level-1"><li><a href="../17784/sl-multiple-choice-tests-on-individual-topics-1.html">SL Multiple choice tests on individual topics</a></li><li><a href="../24351/sl-multiple-choice-quizzes-on-sub-topics-1.html">SL Multiple choice 'quizzes' on sub-topics</a></li><li><a href="../31519/sl-practice-paper-1-exams-1.html">SL Practice Paper 1 exams</a></li><li><a href="../17786/sl-questions-on-each-sub-topic-1.html">SL Questions on each sub-topic</a></li><li><a href="../20431/sl-paper-3-section-a-questions-1.html">SL Paper 3 Section A questions</a></li><li><a href="../17792/sl-questions-on-the-options-1.html">SL Questions on the options</a></li><li><a href="../24897/sl-quizzes-on-option-sub-topics--1.html">SL Quizzes on option sub-topics </a></li><li><a href="../17785/hl-multiple-choice-tests-on-individual-topics-1.html">HL Multiple choice tests on individual topics</a></li><li><a href="../24352/hl-multiple-choice-quizzes-on-sub-topics-1.html">HL Multiple choice 'quizzes' on sub-topics</a></li><li><a href="../31520/hl-practice-paper-1-exams--1.html">HL Practice Paper 1 exams </a></li><li><a href="../17787/hl-questions-on-each-sub-topic--1.html">HL Questions on each sub-topic </a></li><li><a href="../20428/hl-paper-3-section-a-questions-1.html">HL Paper 3 Section A questions</a></li><li><a href="../17793/hl-questions-on-the-options-1.html">HL Questions on the options</a></li><li><a href="../24973/hl-quizzes-on-option-sub-topics-1.html">HL Quizzes on option sub-topics</a></li><li><a href="../41573/printable-versions-of-written-tasks--1.html">Printable versions of written tasks </a></li></ul></li><li><a href="../41465/complete-course-for-students--2.html">Complete course for students </a><ul class="level-1"><li><a 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href="../17160/intermolecular-forces-1.html" title="Intermolecular forces">Intermolecular forces</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24512/mc-test-intermolecular-forces-1.html" title="MC test: Intermolecular forces">MC test: Intermolecular forces</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40937/intermolecular-forces-questions-1.html" title="Intermolecular forces questions">Intermolecular forces questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17237/metallic-bonding-1.html" title="Metallic bonding">Metallic bonding</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24513/mc-test-metallic-bonding-1.html" title="MC test: Metallic bonding">MC test: Metallic bonding</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40939/metallic-bonding-questions-1.html" title="Metallic bonding questions">Metallic bonding questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17260/further-aspects-of-covalent-bonding--1.html" title="Further aspects of covalent bonding ">Further aspects of covalent bonding </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24553/mc-test-further-aspects-of-covalent-bonding-1.html" title="MC test: Further aspects of covalent bonding">MC test: Further aspects of covalent bonding</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40940/further-aspects-of-covalent-bonding-questions-1.html" title="Further aspects of covalent bonding questions">Further aspects of covalent bonding questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17258/hybridization-1.html" title="Hybridization">Hybridization</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24555/mc-test-hybridization-1.html" title="MC test: Hybridization">MC test: Hybridization</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40941/hybridization-questions-1.html" title="Hybridization questions">Hybridization questions</a></li></ul></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../17669/topics-5-15--1.html" title="Topics 5 & 15 ">Topics 5 & 15 </a></li><ul class="level-2 "><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17685/measuring-energy-changes-1.html" title="Measuring energy changes">Measuring energy changes</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24581/mc-test-measuring-energy-changes-1.html" title="MC test: Measuring energy changes">MC test: Measuring energy changes</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39536/measuring-energy-changes-questions--1.html" title="Measuring energy changes questions ">Measuring energy changes questions </a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17689/hesss-law--1.html" title="Hess's Law ">Hess's Law </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24582/mc-test-hesss-law-1.html" title="MC test: Hess's Law">MC test: Hess's Law</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39546/hesss-law-questions-1.html" title="Hess's Law questions">Hess's Law questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17774/bond-enthalpies-1.html" title="Bond enthalpies">Bond enthalpies</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24591/mc-test-bond-enthalpies-1.html" title="MC test: Bond enthalpies">MC test: Bond enthalpies</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39547/bond-enthalpy-questions--1.html" title="Bond enthalpy questions ">Bond enthalpy questions </a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17776/energy-cycles--1.html" title="Energy cycles ">Energy cycles </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24593/mc-test-energy-cycles-1.html" title="MC test: Energy cycles">MC test: Energy cycles</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39569/energy-cycles-questions--1.html" title="Energy cycles questions ">Energy cycles questions </a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17780/entropy-spontaneity--1.html" title="Entropy & spontaneity ">Entropy & spontaneity </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24608/mc-test-entropy-spontaneity-1.html" title="MC test: Entropy & spontaneity">MC test: Entropy & spontaneity</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39650/entropy-spontaneity-questions--1.html" title="Entropy & spontaneity questions ">Entropy & spontaneity questions </a></li></ul></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../17848/topics-6-16-1.html" title="Topics 6 & 16">Topics 6 & 16</a></li><ul class="level-2 "><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17850/collision-theory-rates-of-reaction-1.html" title="Collision theory & rates of reaction">Collision theory & rates of reaction</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24640/mc-test-collision-theory-rates-of-reaction-1.html" title="MC test: Collision theory & rates of reaction">MC test: Collision theory & rates of reaction</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40946/collision-theory-questions-1.html" title="Collision theory questions">Collision theory questions</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40947/rates-of-reaction-questions-1.html" title="Rates of reaction questions">Rates of reaction questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17870/rate-expression-reaction-mechanism-1.html" title="Rate expression & reaction mechanism">Rate expression & reaction mechanism</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24645/mc-test-rate-expression-reaction-mechanisms-1.html" title="MC test: Rate expression & reaction mechanisms">MC test: Rate expression & reaction mechanisms</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40949/rate-expression-questions-1.html" title="Rate expression questions">Rate expression questions</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40950/reaction-mechanisms-questions-1.html" title="Reaction mechanisms questions">Reaction mechanisms questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17876/activation-energy-1.html" title="Activation energy">Activation energy</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24651/mc-test-activation-energy-1.html" title="MC test: Activation energy">MC test: Activation energy</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40954/activation-energy-questions-1.html" title="Activation energy questions">Activation energy questions</a></li></ul></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../18038/topics-7-17--1.html" title="Topics 7 & 17 ">Topics 7 & 17 </a></li><ul class="level-2 "><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18040/equilibrium--1.html" title="Equilibrium ">Equilibrium </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24656/mc-test-equilibrium-1.html" title="MC test: Equilibrium">MC test: Equilibrium</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40959/equilibrium-questions-1.html" title="Equilibrium questions">Equilibrium questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18091/equilibrium-law--1.html" title="Equilibrium law ">Equilibrium law </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24660/mc-test-the-equilibrium-law-1.html" title="MC test: The equilibrium law">MC test: The equilibrium law</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40961/equilibrium-law-questions-1.html" title="Equilibrium law questions">Equilibrium law questions</a></li></ul></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../18120/topics-8-18--1.html" title="Topics 8 & 18 ">Topics 8 & 18 </a></li><ul class="level-2 "><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18124/theories-of-acids-bases--1.html" title="Theories of acids & bases ">Theories of acids & bases </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24662/mc-test-theories-of-acids-bases-1.html" title="MC test: Theories of acids & bases">MC test: Theories of acids & bases</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40963/theories-of-acids-bases-questions-1.html" title="Theories of acids & bases questions">Theories of acids & bases questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18126/properties-of-acids-bases-1.html" title="Properties of acids & bases">Properties of acids & bases</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24663/mc-test-properties-of-acids-bases--1.html" title="MC test: Properties of acids & bases ">MC test: Properties of acids & bases </a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40964/properties-of-acids-bases-questions-1.html" title="Properties of acids & bases questions">Properties of acids & bases questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18140/ph-scale-1.html" title="pH scale">pH scale</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24668/mc-test-the-ph-scale-1.html" title="MC test: The pH scale">MC test: The pH scale</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40971/ph-scale-questions-1.html" title="pH scale questions">pH scale questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18152/strong-weak-acids-bases-1.html" title="Strong & weak acids & bases">Strong & weak acids & bases</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24670/mc-test-strong-weak-acids-bases-1.html" title="MC test: Strong & weak acids & bases">MC test: Strong & weak acids & bases</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40972/strong-weak-acid-bases-questions-1.html" title="Strong & weak acid & bases questions">Strong & weak acid & bases questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18156/acid-deposition-1.html" title="Acid deposition">Acid deposition</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24674/mc-test-acid-deposition-1.html" title="MC test: Acid deposition">MC test: Acid deposition</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40983/acid-deposition-questions-1.html" title="Acid deposition questions">Acid deposition questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18160/lewis-acids-bases-1.html" title="Lewis acids & bases">Lewis acids & bases</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24710/mc-test-lewis-acids-bases-1.html" title="MC test: Lewis acids & bases">MC test: Lewis acids & bases</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40986/lewis-acids-bases-questions-1.html" title="Lewis acids & bases questions">Lewis acids & bases questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18250/acid-base-calculations-1.html" title="Acid base calculations">Acid base calculations</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24714/mc-test-calculations-involving-acids-bases--1.html" title="MC test: Calculations involving acids & bases ">MC test: Calculations involving acids & bases </a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../40988/acid-base-calculations-questions--1.html" title="Acid-base calculations questions ">Acid-base calculations questions </a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../26161/ph-titration-curves-1.html" title="pH titration curves">pH titration curves</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../26158/mc-test-ph-curves-1.html" title="MC test: pH curves">MC test: pH curves</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41000/ph-curves-questions--1.html" title="pH curves questions ">pH curves questions </a></li></ul></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../18350/topics-9-19-1.html" title="Topics 9 & 19">Topics 9 & 19</a></li><ul class="level-2 "><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18365/oxidation-reduction-1.html" title="Oxidation & reduction">Oxidation & reduction</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24725/mc-test-oxidation-reduction-1.html" title="MC test: Oxidation & reduction">MC test: Oxidation & reduction</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41033/oxidation-reduction-questions-1--1.html" title="Oxidation & reduction questions (1) ">Oxidation & reduction questions (1) </a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41034/oxidation-reduction-questions-2-1.html" title="Oxidation & reduction questions (2)">Oxidation & reduction questions (2)</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41035/oxidation-reduction-questions-3-1.html" title="Oxidation & reduction questions (3)">Oxidation & reduction questions (3)</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18383/electrochemical-cells-1.html" title="Electrochemical cells">Electrochemical cells</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24740/mc-test-electrochemical-cells-1.html" title="MC test: Electrochemical cells">MC test: Electrochemical cells</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41072/electrochemical-cells-questions--1.html" title="Electrochemical cells questions ">Electrochemical cells questions </a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18401/electrochemical-cells-ahl--1.html" title="Electrochemical cells (AHL) ">Electrochemical cells (AHL) </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24742/mc-test-electrochemical-cells-ahl-1.html" title="MC test: Electrochemical cells (AHL)">MC test: Electrochemical cells (AHL)</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41098/electrochemical-cells-1-ahl-questions-1.html" title="Electrochemical cells (1) (AHL) questions">Electrochemical cells (1) (AHL) questions</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41099/electrochemical-cells-2-ahl-questions-1.html" title="Electrochemical cells (2) (AHL) questions">Electrochemical cells (2) (AHL) questions</a></li></ul></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../18475/topics-10-20--1.html" title="Topics 10 & 20 ">Topics 10 & 20 </a></li><ul class="level-2 "><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18497/fundamentals-of-organic-chemistry--1.html" title="Fundamentals of organic chemistry ">Fundamentals of organic chemistry </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24749/mc-test-fundamentals-of-organic-chemistry-1.html" title="MC test: Fundamentals of organic chemistry">MC test: Fundamentals of organic chemistry</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41111/fundamentals-of-organic-chemistry-1-questions-1.html" title="Fundamentals of organic chemistry (1) questions">Fundamentals of organic chemistry (1) questions</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41112/fundamentals-of-organic-chemistry-2-questions-1.html" title="Fundamentals of organic chemistry (2) questions">Fundamentals of organic chemistry (2) questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18597/alkanes-alkenes-addition-polymers-1.html" title="Alkanes, alkenes & addition polymers">Alkanes, alkenes & addition polymers</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24750/mc-test-alkanes-alkenes-addition-polymers-1.html" title="MC test: Alkanes, alkenes & addition polymers">MC test: Alkanes, alkenes & addition polymers</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41121/alkanes-questions-1.html" title="Alkanes questions">Alkanes questions</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41124/alkenes-questions-1.html" title="Alkenes questions">Alkenes questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18741/alcohols--1.html" title="Alcohols ">Alcohols </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24772/mc-test-alcohols-1.html" title="MC test: Alcohols">MC test: Alcohols</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41125/alcohols-questions-1.html" title="Alcohols questions">Alcohols questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18742/halogenoalkanes-benzene--1.html" title="Halogenoalkanes & benzene ">Halogenoalkanes & benzene </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24797/mc-test-halogenoalkanes-benzene-1.html" title="MC test: Halogenoalkanes & benzene">MC test: Halogenoalkanes & benzene</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41130/halogenoalkanes-benzene-questions-1.html" title="Halogenoalkanes & benzene questions">Halogenoalkanes & benzene questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18762/nucleophilic-substitution--1.html" title="Nucleophilic substitution ">Nucleophilic substitution </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24757/mc-test-nucleophilic-substitution-1.html" title="MC test: Nucleophilic substitution">MC test: Nucleophilic substitution</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41138/nucleophilic-substitution-questions-1.html" title="Nucleophilic substitution questions">Nucleophilic substitution questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18766/electrophilic-addition--1.html" title="Electrophilic addition ">Electrophilic addition </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24805/mc-test-electrophilic-addition-electrophilic-substitution-reacti-2.html" title="MC test: Electrophilic addition & electrophilic substitution reactions">MC test: Electrophilic addition & electrophilic substitution reactions</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41148/electrophilic-addition-questions-1.html" title="Electrophilic addition questions">Electrophilic addition questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18780/electrophilic-substitution--2.html" title="Electrophilic substitution ">Electrophilic substitution </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41149/electrophilic-substitution-questions-1.html" title="Electrophilic substitution questions">Electrophilic substitution questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18793/reduction-reactions--1.html" title="Reduction reactions ">Reduction reactions </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24811/mc-test-reduction-reactions-1.html" title="MC test: Reduction reactions">MC test: Reduction reactions</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41150/reduction-reactions-questions-1.html" title="Reduction reactions questions">Reduction reactions questions</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18797/synthetic-routes--1.html" title="Synthetic routes ">Synthetic routes </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24822/mc-test-synthetic-routes-1.html" title="MC test: Synthetic routes">MC test: Synthetic routes</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41152/synthetic-routes-questions--1.html" title="Synthetic routes questions ">Synthetic routes questions </a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18844/stereoisomerism--1.html" title="Stereoisomerism ">Stereoisomerism </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24817/mc-test-stereoisomerism-1.html" title="MC test: Stereoisomerism">MC test: Stereoisomerism</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../41166/stereoisomerism-questions-1.html" title="Stereoisomerism questions">Stereoisomerism questions</a></li></ul></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../17285/topics-11-21--1.html" title="Topics 11 & 21 ">Topics 11 & 21 </a></li><ul class="level-2 "><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17276/uncertainty-errors--1.html" title="Uncertainty & errors ">Uncertainty & errors </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24818/mc-test-uncertainties-errors-1.html" title="MC test: Uncertainties & errors">MC test: Uncertainties & errors</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../38869/uncertainty-error-questions--1.html" title="Uncertainty & error questions ">Uncertainty & error questions </a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../15014/graphical-techniques-1.html" title="Graphical techniques">Graphical techniques</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24819/mc-test-graphical-techniques-1.html" title="MC test: Graphical techniques">MC test: Graphical techniques</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39387/graphical-techniques-questions--1.html" title="Graphical techniques questions ">Graphical techniques questions </a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../18968/spectroscopic-identification-of-organic-compounds-1.html" title="Spectroscopic identification of organic compounds">Spectroscopic identification of organic compounds</a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24820/mc-test-spectroscopic-identification-of-organic-compounds--1.html" title="MC test: Spectroscopic identification of organic compounds ">MC test: Spectroscopic identification of organic compounds </a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39388/index-of-hydrogen-deficiency-questions-1.html" title="Index of hydrogen deficiency questions">Index of hydrogen deficiency questions</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39351/identification-from-spectra-question-1-1.html" title="Identification from spectra - Question 1">Identification from spectra - Question 1</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39353/identification-from-spectra-question-2-1.html" title="Identification from spectra - Question 2">Identification from spectra - Question 2</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39354/identification-from-spectra-question-3-1.html" title="Identification from spectra - Question 3">Identification from spectra - Question 3</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39355/identification-from-spectra-question-4-1.html" title="Identification from spectra - Question 4">Identification from spectra - Question 4</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39356/identification-from-spectra-question-5-1.html" title="Identification from spectra - Question 5">Identification from spectra - Question 5</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39357/identification-from-spectra-question-6-1.html" title="Identification from spectra - Question 6">Identification from spectra - Question 6</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39358/identification-from-spectra-question-7-1.html" title="Identification from spectra - Question 7">Identification from spectra - Question 7</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39359/identification-from-spectra-question-8-1.html" title="Identification from spectra - Question 8">Identification from spectra - Question 8</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39360/identification-from-spectra-question-9-1.html" title="Identification from spectra - Question 9">Identification from spectra - Question 9</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39361/identification-from-spectra-question-10-1.html" title="Identification from spectra - Question 10">Identification from spectra - Question 10</a></li></ul><li class=" parent" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../19027/spectroscopic-identification-of-organic-compounds-ahl--1.html" title="Spectroscopic identification of organic compounds (AHL) ">Spectroscopic identification of organic compounds (AHL) </a></li><ul class="level-3 "><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../24821/mc-test-spectroscopic-identification-of-organic-compounds-ahl-1.html" title="MC test: Spectroscopic identification of organic compounds (AHL)">MC test: Spectroscopic identification of organic compounds (AHL)</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39375/identification-from-spectra-question-11-1.html" title="Identification from spectra - Question 11">Identification from spectra - Question 11</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39376/identification-from-spectra-question-12-1.html" title="Identification from spectra - Question 12">Identification from spectra - Question 12</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39377/identification-from-spectra-question-13-1.html" title="Identification from spectra - Question 13">Identification from spectra - Question 13</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39378/identification-from-spectra-question-14-1.html" title="Identification from spectra - Question 14">Identification from spectra - Question 14</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39379/identification-from-spectra-question-15-1.html" title="Identification from spectra - Question 15">Identification from spectra - Question 15</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39380/identification-from-spectra-question-16-1.html" title="Identification from spectra - Question 16">Identification from spectra - Question 16</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39381/identification-from-spectra-question-17-1.html" title="Identification from spectra - Question 17">Identification from spectra - Question 17</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39382/identification-from-spectra-question-18-1.html" title="Identification from spectra - Question 18">Identification from spectra - Question 18</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39383/identification-from-spectra-question-19-1.html" title="Identification from spectra - Question 19">Identification from spectra - Question 19</a></li><li class="" style="padding-left: 42px"><i class="expander fa fa-caret-right "></i><a href="../39385/identification-from-spectra-question-20-1.html" title="Identification from spectra - Question 20">Identification from spectra - Question 20</a></li></ul></ul></ul><li class=" parent" style="padding-left: 0px"><i class="expander fa fa-caret-right "></i><a href="../16441/the-nature-of-science-1.html" title="The Nature of Science">The Nature of Science</a></li><ul class="level-1 "><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../16450/key-terms-concepts-1.html" title="Key terms & concepts">Key terms & concepts</a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../34566/nos-critical-thinking-1.html" title="NOS & Critical Thinking">NOS & Critical Thinking</a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../32100/how-the-elements-were-named-1.html" title="How the elements were named">How the elements were named</a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../36753/the-culture-of-chemistry-1.html" title="The Culture of Chemistry">The Culture of Chemistry</a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../17333/nature-of-science-questions-1.html" title="Nature of Science questions">Nature of Science questions</a></li></ul><li class="ancestor parent" style="padding-left: 0px"><i class="expander fa fa-caret-right fa-rotate-90"></i><a href="../16413/incorporating-im-tok-utilization-etc-1.html" title="Incorporating IM, TOK, 'Utilization' etc.">Incorporating IM, TOK, 'Utilization' etc.</a></li><ul class="level-1 expanded"><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../16414/topic-1-1.html" title="Topic 1">Topic 1</a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../16916/topics-2-12-1.html" title="Topics 2 & 12">Topics 2 & 12</a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../17023/topics-3-13--1.html" title="Topics 3 & 13 ">Topics 3 & 13 </a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../17055/topics-4-14--1.html" title="Topics 4 & 14 ">Topics 4 & 14 </a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../17270/topics-5-15--1.html" title="Topics 5 & 15 ">Topics 5 & 15 </a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../17854/topics-6-16--1.html" title="Topics 6 & 16 ">Topics 6 & 16 </a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../18041/topics-7-17--1.html" title="Topics 7 & 17 ">Topics 7 & 17 </a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../18099/topics-8-18-1.html" title="Topics 8 & 18">Topics 8 & 18</a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../18349/topics-9-19--1.html" title="Topics 9 & 19 ">Topics 9 & 19 </a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../18420/topics-10-20-1.html" title="Topics 10 & 20">Topics 10 & 20</a></li><li class="current" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="topics-11-21--1.html" title="Topics 11 & 21 ">Topics 11 & 21 </a></li></ul><li class=" parent" style="padding-left: 0px"><i class="expander fa fa-caret-right "></i><a href="../17866/utilization-relationships-between-topics--1.html" title="'Utilization' - Relationships between topics ">'Utilization' - Relationships between topics </a></li><ul class="level-1 "><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../17867/relating-topics-4-14-to-all-the-other-topics-1.html" title="Relating Topics 4 & 14 to all the other topics">Relating Topics 4 & 14 to all the other topics</a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../17868/example-of-connections-1.html" title="Example of connections">Example of connections</a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../34404/hydroxychloroquine-ib-chemistry-1.html" title="Hydroxychloroquine & IB Chemistry">Hydroxychloroquine & IB Chemistry</a></li><li class="" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../35418/ammonium-nitrate-ib-chemistry-1.html" title="Ammonium nitrate & IB Chemistry">Ammonium nitrate & IB Chemistry</a></li></ul><li class=" parent" style="padding-left: 0px"><i class="expander fa fa-caret-right "></i><a href="../16685/multiple-choice-tests-for-each-topic-1.html" title="Multiple choice tests for each topic">Multiple choice tests for each topic</a></li><ul class="level-1 "><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../16687/sl-questions-by-topic-1.html" title="SL Questions by topic">SL Questions by topic</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16903/1-stoichiometric-relationships-1--1.html" title="1. Stoichiometric relationships (1) ">1. Stoichiometric relationships (1) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16904/1-stoichiometric-relationships-2--1.html" title="1. Stoichiometric relationships (2) ">1. Stoichiometric relationships (2) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16710/2-atomic-structure-1.html" title="2. Atomic structure">2. Atomic structure</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16738/3-periodicity-1.html" title="3. Periodicity">3. Periodicity</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16822/4-chemical-bonding-structure-1-1.html" title="4. Chemical bonding & structure (1)">4. Chemical bonding & structure (1)</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16823/4-chemical-bonding-structure-2-1.html" title="4. Chemical bonding & structure (2)">4. Chemical bonding & structure (2)</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16887/5-energetics-thermochemistry-1.html" title="5. Energetics & thermochemistry">5. Energetics & thermochemistry</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16906/6-chemical-kinetics-1.html" title="6. Chemical kinetics">6. Chemical kinetics</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17464/7-equilibrium-1.html" title="7. Equilibrium">7. Equilibrium</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17420/8-acids-and-bases-1.html" title="8. Acids and bases">8. Acids and bases</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17416/9-redox-processes-1.html" title="9. Redox processes">9. Redox processes</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17411/10-organic-chemistry-1--1.html" title="10. Organic chemistry (1) ">10. Organic chemistry (1) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17412/10-organic-chemistry-2--1.html" title="10. Organic chemistry (2) ">10. Organic chemistry (2) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17286/11-measurement-data-processing-1--1.html" title="11. Measurement & data processing (1) ">11. Measurement & data processing (1) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17287/11-measurement-data-processing-2-1.html" title="11. Measurement & data processing (2)">11. Measurement & data processing (2)</a></li></ul><li class=" parent" style="padding-left: 14px"><i class="expander fa fa-caret-right "></i><a href="../16688/hl-questions-by-topic-1.html" title="HL Questions by topic">HL Questions by topic</a></li><ul class="level-2 "><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16709/1-stoichiometric-relationships-1-1.html" title="1. Stoichiometric relationships (1)">1. Stoichiometric relationships (1)</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16735/1-stoichiometric-relationships-2-1.html" title="1. Stoichiometric relationships (2)">1. Stoichiometric relationships (2)</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../37016/2-12-atomic-structure-1-1.html" title="2 &12. Atomic structure (1)">2 &12. Atomic structure (1)</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16721/2-12-atomic-structure-2-1.html" title="2 &12. Atomic structure (2)">2 &12. Atomic structure (2)</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16815/3-13-periodicity-transition-metals-1--1.html" title="3 & 13. Periodicity & transition metals (1) ">3 & 13. Periodicity & transition metals (1) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16816/3-13-periodicity-transition-metals-2--1.html" title="3 & 13. Periodicity & transition metals (2) ">3 & 13. Periodicity & transition metals (2) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16861/4-14-chemical-bonding-structure-1-1.html" title="4 & 14. Chemical bonding & structure (1)">4 & 14. Chemical bonding & structure (1)</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16862/4-14-chemical-bonding-structure-2-1.html" title="4 & 14. Chemical bonding & structure (2)">4 & 14. Chemical bonding & structure (2)</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16894/5-15-energetics-thermochemistry-1--1.html" title="5 & 15. Energetics & thermochemistry (1) ">5 & 15. Energetics & thermochemistry (1) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../16893/5-15-energetics-thermochemistry-2--1.html" title="5 & 15. Energetics & thermochemistry (2) ">5 & 15. Energetics & thermochemistry (2) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17654/6-16-chemical-kinetics-1--1.html" title="6 & 16. Chemical kinetics (1) ">6 & 16. Chemical kinetics (1) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17655/6-16-chemical-kinetics-2--1.html" title="6 & 16. Chemical kinetics (2) ">6 & 16. Chemical kinetics (2) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17471/7-17-equilibrium-1--1.html" title="7 & 17. Equilibrium (1) ">7 & 17. Equilibrium (1) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17472/7-17-equilibrium-2--1.html" title="7 & 17. Equilibrium (2) ">7 & 17. Equilibrium (2) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17421/8-18-acids-bases-1--1.html" title="8 & 18. Acids & bases (1) ">8 & 18. Acids & bases (1) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17422/8-18-acids-bases-2--1.html" title="8 & 18. Acids & bases (2) ">8 & 18. Acids & bases (2) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17417/9-19-redox-processes-1--1.html" title="9 & 19 Redox processes (1) ">9 & 19 Redox processes (1) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17418/9-19-redox-processes-2--1.html" title="9 & 19. Redox processes (2) ">9 & 19. Redox processes (2) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17413/10-20-organic-chemistry-1--1.html" title="10 & 20. Organic chemistry (1) ">10 & 20. Organic chemistry (1) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17415/10-20-organic-chemistry-2--1.html" title="10 & 20. Organic chemistry (2) ">10 & 20. Organic chemistry (2) </a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17288/11-21-measurement-data-processing-analysis-1-1.html" title="11 & 21. Measurement, data processing & analysis (1)">11 & 21. Measurement, data processing & analysis (1)</a></li><li class="" style="padding-left: 28px"><i class="expander fa fa-caret-right "></i><a href="../17289/11-21-measurement-data-processing-analysis-2--1.html" title="11 & 21. Measurement, data processing & analysis (2) ">11 & 21. Measurement, data processing & analysis (2) </a></li></ul></ul></ul></nav></div><!-- /#left-column-->
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</div><section id="main-content"><div id="toc-1672969633" class="toc"><a href="#" class="toc-switcher" title="Show table of contents"><small><i class="fa fa-reorder"></i> Table of contents <span class="pull-right"><i class="fa fa-chevron-down"></i></span></small></a></div><h1><strong>Including International-mindedness, TOK, and 'Utilization' in Measurement, data processing & analysis</strong></h1><div class="blueBg"><h2><strong>International-mindedness</strong></h2><p><img class="ico" src="../../../img/icons/standard-1.png"> <img class="ico" src="../../../img/icons/higher-1.png"> <strong>What are the 'true' values of units?</strong></p><p><img alt="" class="noborder right" height="175" src="../../../ib/chemistry/images/Core and AHL/Topic 11 uncertainty/Platinum-Iridium_meter_bar.jpg" title="An alloy bar made from 90% platinum and 10% iridium (Image from Wikimedia commons)" width="270">The units that chemists use are international. A mole is the same worldwide. The SI unit of volume is a cubic metre although in practice a more useful unit is a cubic decimetre, dm<sup>3</sup> which is called a litre in many countries. In the syllabus, and in examination questions, the IB uses dm<sup>3</sup> and also cm<sup>3</sup><sup> </sup>but students who use litre, l, and millilitre, ml, respectively are not penalised as these are perfectly correct ways of expressing units of volume in many countries. How accurately are these units known and what is their ‘true’ value? For a metre the ‘true’ value was originally defined in France in 1793. It was further defined in 1889 as the distance between two lines marked on a bar composed of an alloy of platinum and iridium (90% Pt and 10% Ir) and this bar is still kept under specified conditions in the <em>Bureau International des Poids et Mesures</em> in Sevres, France (see image).</p><p>As measurements became more precise and accurate this standard for the metre was insufficient. In 1960 it was redefined as equal to 1,650,763.73 wavelengths of the orange-red emission line in the electromagnetic spectrum of <sup>86</sup>Kr in a vacuum. Since 1983 a metre has been further defined as "the length of the path travelled by light in vacuum during a time interval of 1/299,792,458 of a second." This reduces uncertainty even further but now, of course, this definition also depends on the accurate definition of a second!<br><br>Similar redefining has taken place with the definition of a mole and the atomic mass of an element. Because of advantages in analytical chemistry atomic masses can now be measured much more precisely than in the past. This has led to <a href="chemistry/blog/8075/atomic-masses-changechemistry/blog-post/8075/atomic-masses-change.htm">a recent change in the atomic mass of eleven elements.</a> For these elements, which occur naturally as more than one isotope, the atomic mass is now given as lying between two values. For example, the range for hydrogen is now given as 1.007 84 to 1.008 11. For chemistry at IB level, where generally values to three significant figures (or for atomic mass two decimal places) are used, these changes in volume and atomic mass are irrelevant. However for precise work particularly when dealing with the chemistry of other galaxies where large distances and time are involved these changes can make a significant difference. Even with these precise values for a metre and atomic numbers it is still worth noting that none of them comes with the IB + or – uncertainty that our students are supposed to always provide with their experimentally determined results!</p><hr class="hidden"></div><hr class="hidden"><div class="greenBg"><h2>Theory of knowledge</h2><p>The whole topic of measurement and uncertainty is inherently concerned with TOK since we could ask how can we be certain of anything if there is an uncertainty associated with all quantitative measurements upon which conclusions are based?</p><hr class="hidden"><p><img class="ico" src="../../../img/icons/standard-1.png"> <img class="ico" src="../../../img/icons/higher-1.png"> <strong>1. What is the accepted 'literature value'?</strong></p><p>When writing their conclusion for their assessed individual scientific investigation students are encouraged to compare their result with the 'literature value' and hence deduce their percentage error and use this as the basis to evaluate the validity or otherwise of their experimental method. The literature value is often obtained from a data book. There are two comments to make here. The first is that different data books often quote different values. For example, consider the values given for the boiling point of cyclohexene from reputable data books and text books:</p><p style="margin-left: 160px;">82.98 <sup>o</sup>C<sup>1</sup><br>83.3 <sup>o</sup>C<sup>2</sup><br>83 <sup> </sup><sup>o</sup>C<sup>3</sup></p><p><sup>1.</sup> D.R. Lide (Ed.), Handbook of Chemistry & Physics, 88th. Ed., CRC Press, 2007<br><sup>2.</sup> J.G. Stark & H.G.Wallace, Chemistry Data Book, 2nd. Ed., John Murray, 1989<br><sup>3.</sup> R.T. Morrison & R.N. Boyd, Organic Chemistry, 6th. Ed., Prentice-Hall, 1992</p><p>Students of course will often go to the Internet to obtain the literature value. <a href="http://en.wikipedia.org/wiki/Cyclohexene">Wikepedia</a> lists 82.98 <sup>o</sup>C, which is presumably taken from the CRC book. However the reputable website from the RSC, <a href="http://www.chemspider.com/Chemical-Structure.7788.html">ChemSpider</a> lists many values:</p><p style="margin-left: 160px;">82 °C/mmHg (<span></span><a href="http://www.tcichemicals.com/eshop/en/gb/commodity/C0491" target="_new">Tokyo Chemical Industry Ltd</a>)</p><p style="margin-left: 160px;">83-85 deg C<span> </span>(Alfa Aesar)</p><p style="margin-left: 160px;">83-85 deg C / mmHg<span> </span>(Alfa Aesar)</p><p style="margin-left: 160px;">181F (<span></span><a href="http://www.cdc.gov/niosh/npg/npgd0167.html" target="_new">NIOSH</a>)</p><p style="margin-left: 160px;">80.7 C<span> </span>(Fisher MSDS)</p><p>Clearly there are many different values given (including a difference in the number of significant figures) so which is the true one upon which students should work out their percentage error? The second point is that although the IB insists on students giving the uncertainty associated with their calculated result this is obviously not how science works in reality since <strong>none</strong> of the literature values come with any associated uncertainty.</p><hr class="hidden"><p><img class="ico" src="../../../img/icons/standard-1.png"> <img class="ico" src="../../../img/icons/higher-1.png"> <strong>2. Heisenberg's Uncertainty Principle</strong></p><p>It is worth stressing to students that not only is there an uncertainty due to the apparatus or instrument used to take any measurement but there is an inherent uncertainty in the system itself. Any attempt to make a measurement actually affects what is being measured. The more accurately the position of a particle is known the less accurately its momentum is known and <em>vice-versa</em>. For very small particles such as electrons this effect is significant but it is even present, although to a much less significant extent, for particles with greater mass.</p><hr class="hidden"></div><hr class="hidden"><div class="pinkBg"><h2>'Utilization'</h2><p>The syllabus makes several references to utilizing spectroscopic techniques. For example magnetic resonance imaging (MRI) which gives a three-dimensional view of organs in the human body and asks why MRI is replacing computerized tomography (CT) scans for some applications but is used as a complementary technique for others. It also mentions the forensic applications of chromatography and spectroscopy and the use of analytical techniques for drug testing. Under topic 11 it mentions the problems with the incorrect measurement of the speed of neutrinos when scientists at CERN <a href="chemistry/blog/10817/e-mc-a-little-bit2">pronounced that the neutrinos were travelling faster than the speed of light</a> and the crash of the Mars Climate Orbiter spacecraft (see below). Under graphing in <a href="../15014/graphical-techniques-1.html" title="Core & AHL » Teaching each topic & sub-topic » Topics 11 & 21 » Graphical techniques">11.2</a> it includes using graphical data in areas such as population, finance and climate modelling. The statistical trends can lead to predictions and to the underpinning of government policies in areas such as health and education. Some particular examples of utilization are:</p><hr class="hidden"><p><img alt="smiley" class="ico" height="16" src="../../../img/tib-icons/standard-level-16-1.png" title="smiley" width="16"> <img class="ico" src="../../../img/icons/higher-1.png"> <strong>1. Global warmin</strong>g</p><p><img alt="" class="noborder" src="../../../ib/chemistry/images/2014%20Core%20%26%20AHL/Topics%2011%20%26%2021/monthly-levels-of-co2-up-to-2023.png" style="float: right; width: 400px; height: 290px;">Is the current global warming man-made? It seems to be generally accepted by informed people now that the increase in the combustion of fossil fuels since the industrial revolution has led to an increase in the carbon dioxide concentration in the atmosphere. There has also been an increase in global warming due to the greenhouse effect. There is good scientific evidence from the <a href="http://www.esrl.noaa.gov/gmd/ccgg/trends/">Mauna Loa Observatory, in Hawaii</a> that carbon dioxide levels have increased (and are still increasing - see graph on left) and that the average temperature of the Earth has increased during the past century but there is no certainty at all, just informed speculation, that this is all due to just human activities.</p><hr class="hidden"><p><img class="ico" src="../../../img/icons/standard-1.png"> <img class="ico" src="../../../img/icons/higher-1.png"> <strong>2. Food and drug research</strong></p><p>Often research is quoted in newspapers and online about how particular foods are good or bad for your health. For example, one study in 2013 published in the <a href="http://aje.oxfordjournals.org/content/early/2012/12/09/aje.kws222.abstract">American Journal of Epidemiology</a>, found that drinking coffee is associated with a reduced risk of oral cancer. This study was made from data obtained from 968,432 individuals and the uncertainty associated with the outcome is listed. Contrast this to some claims made by supposedly independent research into other foodstuffs and drugs. For example, a team of researchers led by Dr Robert McNamara at the University of Cincinnati, USA, <a href="http://www.ajcn.org/cgi/content/abstract/91/4/1060?maxtoshow=&hits=10&RESULTFORMAT=&fulltext=McNamara&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT">reported in 2010</a> in the American Journal of Clinical Nutrition that boys aged 8-10 who take daily dosages of docosahexaenoic acid showed a big improvement in their ability to concentrate and in their performance doing tasks that involved attention. This research involves just 33 individuals who were not randomly selected and the research was paid for by the company that produces the fish oil containing the docosaheaxaenoic acid. How high is the uncertainty associated with such results? You can read more about this in my <a href="chemistry/blog-post/3152/fish-oil-.htm">blog article</a>.</p><hr class="hidden"><p><img alt="smiley" class="ico" height="16" src="../../../img/tib-icons/standard-level-16-1.png" title="smiley" width="16"> <img alt="laugh" class="ico" height="16" src="../../../img/tib-icons/higher-level-16-1.png" title="laugh" width="16"> <strong>3. Mars Climate Orbiter spacecraft</strong></p><p>In 1998 NASA launched a robotic space probe called the Mars Climate Orbiter which was intended to study the Martian climate. However nine months later communication with the spacecraft was lost as they tried to programme it to go into orbit around Mars. The spacecraft eventually disintegrated in the upper atmosphere of Mars as it was on the wrong trajectory which took it too close to the planet. The reason was because the computer software used on the ground was programmed in the non-SI units of pound-seconds whereas the onboard computers were operating in the different units of newton seconds.</p><hr class="hidden"><p><img alt="smiley" class="ico" height="16" src="../../../img/tib-icons/standard-level-16-1.png" title="smiley" width="16"> <img alt="laugh" class="ico" height="16" src="../../../img/tib-icons/higher-level-16-1.png" title="laugh" width="16"> <strong>4. Testing athletes for drugs</strong></p><p><img alt="" class="noborder right" height="220" src="../../../ib/chemistry/images/2014 Core %26 AHL/Topics 11 %26 21/Ben Johnson.jpg" title="Ben Johnson - image from Guardian newspaper (http://static.guim.co.uk/sys-images/Guardian/Pix/pictures/2012/5/23/1337772628902/sport-006.jpg)" width="150">Testing for drugs is now an integral part of any major sporting event. Two of the most famous athletes who have been caught cheating are the 100 m sprinter <a href="http://en.espn.co.uk/onthisday/sport/story/283.html">Ben Johnson</a> (see image on right) and <a href="http://www.telegraph.co.uk/sport/othersports/cycling/lancearmstrong/10975799/Lance-Armstrong-holds-seven-hour-talks-with-doping-investigators-as-he-gives-evidence-about-drugs-in-cycling.html">Lance Armstrong</a>, the seven times winner of the Tour de France cycle race.<br>Both urine and blood samples from athletes (and race horses) are tested for a huge range of banned substances. Probably the main method of determining the presence and amount of a banned substance in the body is gas liquid chromatography linked to mass spectrometry (GLC-MS). The GLC separates the substances present in a urine sample according to their retention times and then they pass through a mass spectrometer where their spectra are compared with a database of known samples. Another technique that is sometimes used for specific substances is immuno-assay. 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