Title |
MISCONCEPTIONS IN THE CHEMISTRY TEACHING IN THE REPUBLIC OF MACEDONIA REGARDING THE OXIDATION REACTIONS OF MONOSACCHARIDES |
Author/s |
Marina Stojanovska, Bojan Šoptrajanov, Vladimir M. Petruševski |
Citation |
M. Stojanovska, B. Šoptrajanov, and V. M. Petruševski, "MISCONCEPTIONS IN THE CHEMISTRY TEACHING IN THE REPUBLIC OF MACEDONIA REGARDING THE OXIDATION REACTIONS OF MONOSACCHARIDES", Contributions, Sec. Nat. Math. Biotech. Sci., MASA, ISSN 1857-9027, Vol. 34, no.1-2, 2013, pp.27-32. |
Abstract |
The easy oxidation of the substances containing aldehyde groups using a mild oxidizing agents, such as
solutions containing copper(II) or silver(I) ions, can provide a mean to detect the presence of carbohydrates known as
reducing sugars. However, using such tests, it is not possible to distinguish between aldoses and ketoses because the
alkaline conditions in the reaction system lead to tautomerization of the α-hidroxyketone and immediate oxidation of
the product so that both glucose and fructose will react with the oxidizing agents (the Tollens’ and Fehling’s
reagents). In fact, the reaction of fructose is even faster than that of glucose. A misinterpretation or simple neglect of
these experimental facts is present in some textbooks in the Republic of Macedonia and this influences the chemistry
teaching by creating misconceptions among students and teachers.
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Keywords |
misconceptions; monosaccharides; Tollens’ and Fehling’s reagents; reducing sugars; chemistry teaching |