In this research, the contents of electrolytes in high school science textbooks are analyzed and
related problems are identified.
First of all, we collected 201 on line questions about chemistry from high school students,
and classified the questions into 6 groups according to subjects. The results demonstrated that
questions regarding the “material” subject are the most with 37.8% of 201 questions. Questions
on the “electrolytes and ions” are the most, 76.3% among the questions regarding “materials”.
As a result, the question about “ionization of electrolytes” are the most with 32.8% among the
questions regarding “electrolytes and ions”.
On the basis of the concept map of material found, we made “Sematic Networking
(SemNet)” out electrolyte concept. We could find 6 relations between concepts from SemNet. 『electrolytes are classified with weak electrolyte and strong electrolyte.』, 『If an electrolyte is
dissolved in water, it makes cation and anion.』, 『Example of electrolyte is NaCl, HCl,
CH3COOH, H2CO3(ionic compound and molecular compound).』, 『If the electric current flows
in the electrolytic aqueous solution, electrolysis occurs.』, 『electrolyte consists of ionic bond or
polar covalent bond materials.』, 『The electric current flowing in the electrolytic aqueous
solution is due to oxidation and reduction reaction.』. For 6 relations between concepts, the
content of textbooks were analyzed and evaluated.
In relation with ionization of electrolytes, we analyzed 11 high school science textbooks. In
most textbooks the “electrolyte” is described only in terms of ionic compounds instead of being
described in both terms of ionic compounds and molecular compounds. Also, we graded 11
textbooks by the standard of 2 items. As a result, “B” textbook\'s description is the most
superior regarding ionization of electrolytes.