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The HIPST project was created to provide ideas and resources for teaching of History and Philosophy of Science for Teaching.It is funded by the EU and directed from Germany. Seven other countries are involved: Israel, Greece, Portugal, Italy, Hungary, Poland and the UK. It started in February 2008 and will close with international publication in July 2010.

UK
The UK Principal Investigator is Dr John Oversby, Reading University. This web site is a part of the resources for trialling the project in 2009. It focuses on the place of ideas change in scientific development. The context is acidity.

Acidity represents all of the three forms of representation in chemistry: macroscopic, sub-microscopic and symbolic. there is a time-line progression of ideas about acidity that can be partly interpreted at paradigm change.


 * Macroscopic**: this approach is concerned principally with how acids behave, with demarcation of the concept of acidity in terms of phenomena observation, a philosophical process. It is difficult to establish exactly when it began, since the roots of acids are embedded in history, especially with their sour taste, supported by the etymology in different languages (e.g. 1626, from Fr. acide, from L. acidus "sour," adj. of state from acere "to be sour," from PIE base *ak- "sharp, pointed" (see [|acrid]) and alkali c.1386, "soda ash," from M.L. alkali, from Arabic al-qaliy "the ashes" (of saltwort, a plant growing in alkaline soils), from qalay "to roast in a pan." The modern chemistry sense is from 1813. Alkaline is attested from 1677) [Online Etymological Dictionary] Robert Boyle was central to the development of indicators to identify acidity. Later, chemists tried to find the 'magic ingredient' that made an acid what it is. Lavoisier thought this was oxygen. The existence of acids not containing oxygen was, in itself, sufficient to overthrow this idea, but, although Berthollet had shown, in 1789, that sulphuretted hydrogen (or hydrosulphuric acid) contained no oxygen, Lavoisier's theory held its own until the researches of Davy, [|Gay-Lussac] and Thenard on [|hydrochloric acid] and [|chlorine], and of Gay-Lussac on hydrocyanic acid, established beyond all reasonable dpoubt that oxygen was not essential to acidic properties. Oxides of metals were bases which could [|neutralise] oxides of metals to make salts (from Old Englis sealt, meaning sea and similar to Greek halos meaning sea). This was part of the [|dualistic] paradigm of chemistry. Liebig was one of the earliest to announce the hydrogen idea of acidity, largely resulting from his study of different phosphoric acids.


 * Sub-microscopic**: Nicholas [|Lemery] in 1680 proposed his theory that acids had [|corpuscles,] or little objects, with sharp points that pricked the tongue, leading to the sensation of sourness. His very strict religious views (he was a Calvinist) meant that he had to give up his pharmacy and lectures in Paris in 1683 and move to England. In 1684 he returned to France and became a Catholic in 1687, and able to return to his pharmacy and lectures. He was a practical chemist, dealing with facts and demonstrations, rather than the more theoretical speculations of the alchemists (alchemist from [|Old French] [|alkemie], [|arquemie] (French [|alchimie] ) < [|Mediaeval Latin] [|alkimia] < [|Arabic] [|الكيمياء] ( al-kīmiyā’ ) < article [|al] +[|Ancient Greek] [|χημεία] or [|χυμεία] ( chēmeia or chymeia ) - searching for the ultimate panacea (1548, from L. panacea, an all-healing herb, from Gk. panakeia "cure-all," from panakes "all-healing," from pan- "all" + akos "cure," from iasthai "to heal." Earlier in Eng. as panace (1513).

SO3 and hydrogen in HCl. In the case of other formulae as in CH3COOH, it may not be possible without further knowledge to know whether this is an acid, and which hydrogen atoms are responsible. Chemical equations give different levels of representation, such as word equations, such as sodium hydroxide + hydrochloric acid --> sodium chloride + water and concept equations such as alkali + acid --> salt + water A variety of other, chemical formulae-type, equations also exist and these will be examined in the Scheme of Work.
 * Symbolic**: Symbolic representation of acids may indicate the place of the 'magic component' such as oxygen in