Module 8: Applying Chemical Ideas
10 dot points across 3 inquiry questions, in syllabus order. Each dot point has a focused answer, with exam-style questions and worked answers where available.
Inquiry Question 1: How are the ions present in the environment identified and measured?
Instrumental concentration measurement. The Beer-Lambert law, building and using a calibration curve, when to choose colourimetry vs UV-vis vs AAS, how AAS uses a hollow-cathode lamp to reach part-per-billion detection of metals, and worked HSC past exam questions.
Qualitative ion identification. Flame tests for group 1 and 2 cations, precipitation tests for transition metals and halides, complexation tests for copper, iron and silver, a structured systematic analysis, and worked HSC past exam questions.
Quantitative wet-chemistry analysis. The full gravimetric workflow (precipitate, filter, dry, weigh), worked sulfate-as-barium-sulfate calculation, the Mohr precipitation titration of chloride with silver nitrate, sources of error, and worked HSC past exam questions.
Environmental monitoring. Why we measure cation and anion concentrations in air, water and soil, the legal and health thresholds involved, the difference between qualitative and quantitative analysis, and worked HSC past exam questions.
Inquiry Question 2: How is information about the reactivity and structure of organic compounds obtained?
Qualitative tests for organic functional groups. The bromine water and acidified permanganate tests for C=C, the sodium and acidified dichromate tests for hydroxyl, the sodium carbonate and reactive metal tests for carboxylic acids, a flowchart for an unknown, and worked HSC past exam questions.
Infrared spectroscopy. How bond vibrations absorb IR radiation, the diagnostic absorption ranges for O-H, N-H, C=O, C-H and C=C, how to read an IR spectrum to identify functional groups, the role of the fingerprint region, and worked HSC past exam questions.
Mass spectrometry. The five stages of a mass spectrometer (ionisation, acceleration, deflection, detection, recording), how to read a mass spectrum, identifying the molecular ion and the base peak, recognising fragment loss of 15, 17, 29, 45, the M+2 isotope pattern of chlorine and bromine, and worked HSC past exam questions.
NMR spectroscopy. How spin-half nuclei resonate in a strong magnetic field, the four features of a proton NMR spectrum (number of signals, chemical shift, integration, multiplicity via the n+1 rule), carbon-13 chemical shift ranges, the role of TMS, and worked HSC past exam questions.
Inquiry Question 3: How, and why, are chemical reactions used to produce particular products?
Haber and contact processes. How Le Chatelier's principle and collision theory are balanced against each other to set industrial temperature, pressure and catalyst choices, worked equilibrium and yield calculations, and graded HSC-style practice questions.
Chemical synthesis design. The factors a chemist must consider (reagent availability, reaction conditions, yield and purity, by-products, energy, environmental and economic issues), green chemistry principles, the case of aspirin synthesis as a worked example, and HSC past exam questions.