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Screen titration analysing hair dye

The RSC's screen titration experiment (level 1 explored in Titrations) has further titration simulations that give contexts and activities to combinations or strong/weak acids/alkalis. The scenario in level 3 is about a haul of counterfeit cosmetics, where hair dye that has been seized has to be tested to check the level of ammonia in the product as it may be above the limit allowed by Trading Standards. The simulation shows the chemistry and equilibrium for this example of a weak base and its conjugate acid. Further discussion of the chemistry of hair dye is given in Education in Chemistry.

Hydrofluoric acid chemistry in tv thriller – podcast and student feature

Listen to the podcast (or read the transcript) about hydrofluoric acid and why, for a weak acid, it demands the greatest care and respect.  The RSC's student magazine, The Mole, highlights the chemistry of HF in a concise feature article also explaining its role in TV's Breaking Bad series.

Balls of Fire

This spectacular demonstration, available with video, instructions and teaching points, involves the acid-base reaction of potassium manganate(VII) (KMnO₄) with sulfuric acid to produce permanganic acid (HMnO₄) which spontaneously dehydrates with sulfuric acid to form manganese(VII) oxide (Mn₂O₇) on the end of a glass rod. It reacts violently with carbon compounds, shown here with cotton wool.  Some tips for discussing the conjugate acid-base pairs and Ka manipulation are given.

Textbooks’ and teachers’ understanding of acid-base models used in chemistry teaching

This journal article from Chemistry Education Research and Practice, 2005, provides educational research regarding teaching theories of acidity centred around secondary schools in Sweden. It provides useful insights into the use of these models in schools and encourages a more critical look at text books and how they are used, particularly in this topic of theories of acidity.