A Closer Look at Trends in Boiling Points of Hydrides: Using an Inquiry-Based Approach to Teach Intermolecular Forces of Attraction

Autor/inn/en	Glazier, Samantha; Marano, Nadia; Eisen, Laura
Titel	A Closer Look at Trends in Boiling Points of Hydrides: Using an Inquiry-Based Approach to Teach Intermolecular Forces of Attraction
Quelle	In: Journal of Chemical Education, 87 (2010) 12, S.1336-1341 (6 Seiten)Infoseite zur Zeitschrift PDF als Volltext Verfügbarkeit
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	0021-9584
DOI	10.1021/ed100691n
Schlagwörter	Thermodynamics; Chemistry; Interaction; Data Analysis; Scientific Principles; Science Instruction; Molecular Structure; Heat; Introductory Courses; Science Activities + Suchen Sie Ihr Suchwort? Thermodynamik; Chemie; Interaktion; Auswertung; Teaching of science; Science education; Natural sciences Lessons; Naturwissenschaftlicher Unterricht; Hitze; Einführungskurs
Abstract	We describe how we use boiling-point trends of group IV-VII hydrides to introduce intermolecular forces in our first-year general chemistry classes. Starting with the idea that molecules in the liquid state are held together by some kind of force that must be overcome for boiling to take place, students use data analysis and critical reasoning to discover different types of intermolecular forces. In general, dispersion forces provide the largest contribution to the strength of the total intermolecular interaction energy, whereas dipole forces add only a small contribution, except in the case of molecules that can form hydrogen bonds. We discuss the thermodynamics of boiling and why it is legitimate to use boiling point as a measure of intermolecular forces. Finally, we examine the choice of variable to use on the x axis when graphing boiling point. Although the molecular polarizability may be a good variable to use, because it is the largest component of the interaction energy, the number of electrons is sufficiently well correlated with polarizability to recommend using boiling point versus number of electrons as the best compromise for introductory chemistry classes. (Contains 1 table, 5 notes and 5 figures.) (As Provided).
Anmerkungen	Division of Chemical Education, Inc and ACS Publications Division of the American Chemical Society. 1155 Sixteenth Street NW, Washington, DC 20036. Tel: 800-227-5558; Tel: 202-872-4600; e-mail: eic@jce.acs.org; Web site: http://pubs.acs.org/jchemeduc
Erfasst von	ERIC (Education Resources Information Center), Washington, DC
Update	2017/4/10