IB Chemistry/Extended Essay

Suggestions

Here is a list of suggestions for Science Investigations. Please add/amend/extend the list as you see fit. This is essentially a brainstorm...

Non-coalescing drops

Some industries will mix liquids by cascading one liquid into another, assuming mixing will be complete. These drops may prevent complete mixing and need to be investigated.

Recent research has shed light on this phenomenon: The fast-moving shiny drops that skid across the surface of soapy water. Detergents play a crucial role – but how does the concentration of detergent affect the drops? What about ‘non-ionic’ detergents? What about a surface of anionic detergents and drops of cationic ones?

Challenges: Making drop-producing apparatus, Researching the chemistry of detergents, Assessing the numbers of drops

Thiosulphate/acid reaction (‘disappearing cross’)

Chemical engineers wishing to check if turbidity is a useful surrogate measurement for whether a reaction has reached completion.

How does the reaction respond to changes in acid concentration (it is first order for thiosulphate concentration but varies from first to zero order with acid).

How can we assess the amount of oil contamination on beaches?

Various groups will want to assess oil contamination, and a simple quick method would be appreciated.

The method used solvent extraction. Sand samples were laced with oil and the efficiency of recovery was measured. The sensitivity of the method was also estimated.

Synthesis and isolation of propanoic acid from propan-1-ol.

Chemical suppliers who want to investigate production of this chemical.

Trialling different methods.

Making biodiesel from waste vegetable oil.

Motoring enthusiasts who want to make their own environmentally-friendly and cheap fuel.

By using methanol and sodium hydroxide it is possible to make diesel fuel from old chip fat.

Analysing the gases remaining after burning a candle in a gas jar.

Motor vehicle engineers who want to check the composition of exhaust gases.

CO₂ is easy; it is readily absorbed with NaOH.

O₂ is harder; an oxygen probe is very useful but otherwise oxygen could be absorbed by, for example, the slow reaction of steel wool.

CO is challenging; it will be absorbed by CuCl solution but it is in very low concentrations.

Extraction of caffeine from tea.

Suppliers or independent analysts want to assess the caffeine content of tea products. Chemical suppliers want to provide pure caffeine to clients.

This method usually involves solvent extraction with a chlorinated alkane (e.g. dichloromethane or 1,1,1,-trichloroethane). With care it is possible to recycle the solvent and avoid health and environmental damage.

Other suggestions

• Investigation of weak acid strengths/synthesis of new acids

• Rate expression for tin/iodine reaction – kinetics of a reaction

• Nobili’s rings – strange colours seen during electrolysis.

• A transient red colour – the chemistry of iron/sulphate complexes.

• Liesegang rings – stripey effects in gels.

• Polarimetry to investigate concentrations of sugars. Suppliers of sugar syrups who want to assess their products.

• Flame photometry to determine concentrations of aqueous ions. Analysis of mineral water samples to check manufacturers' claims.

• Is the level of chloramines found in swimming pool water affected by temperature? Swimming pool operators concerned about eye irritation amongst their customers.

• Effectiveness of two major washing powders on five common household stains. Consumer testing organisation who wants to test commercial claims.

• Factors affecting the decomposition of biodegradable plastics. Environmental agencies testing claims of environmental-friendliness from plastics manufacturers.

• Studies of infrared spectroscopy: nature and applications. Applications include breath-testing for alcohol and testing vehicle exhaust emissions.

• NaCl and potential alternatives to NaCl as a roadway de-icer. Highways agency investigating de-icers which cause less environmental damage - but at what cost?

• Synthesis and analysis of hexane-3,4-diol.

• Calcium carbonate content of seashells.

• Characterisation of New Polyethylenes Prepared by Single-Site Catalysis.

• An Investigation Into The Uses Of Environmentally Friendly Additives/Alternatives To Petrol.

• Protein Purification.

• A study into the colour of ketchup.

• Comparison By Spectral Characterisation Of Myoglobin In Beef, Pork and Turkey.

• Spectrophotometric Determination of Trace Amounts of Iron in Plant Samples.

• The effect of disulphide reduction on the structure, and activity of Yeast Alcohol Dehydrogenase.

• Investigation into the effect of pH on the mechanism of glycation of phenylalanine as a model of the glycation of the B chain of insulin.

• Analysis of Vitamin C in Orange Juice through a Chemiluminescent Clock Reaction.

• Investigating the Effect of Different Halide Ions on the Stern Volmer Constant.

• Developing and Validating an Assay for Tissue Thiols and the Analysis of the Effects of Aging and Taurine on Tissue Thiols.

• Relation between the Slow Relaxation Time and Foaming of Selected ICI Surfactants.

• Purification of ibuprofen from commercial tablets.

• Building a breathalyser.g

• Titration of various commercial vinegar samples.

• Titration of vitamin C content of commercial fruit juices.

• Investigation in the synthesis of acetylsalicylic acid (aspirin).