ChemPrep was developed to be a stand-alone preparatory short-course to help students succeed in general chemistry. It is Web-based and delivered using the OWL system. Students reported that the ChemPrep materials (short information pages, parameterized questions with detailed feedback, tutorials, and answers to questions through the OWL message system) permitted them to work independently without the need for textbook or lecture. On average, students who completed ChemPrep had higher grades in the subsequent GenChem, Nursing, and Honors chemistry courses, with a greater percentage achieving a grade of C- or higher. Participation in ChemPrep was voluntary, and more women than men responded. Students in the Honors course enrolled in ChemPrep in higher percentages than students in GenChem and Nursing. SAT and departmental math placement exam scores were used as proxy measures of prior achievement and ability. Based on these, Honors chemistry ChemPrep users were on par with their peers but performed better in the course than non-users. In GenChem and Nursing chemistry courses, ChemPrep helped students of high prior achievement and ability perform better than their achievement scores would predict. Weaker or less motivated students did not respond to the voluntary offerings of ChemPrep in the same numbers as stronger or more motivated students, and we are seeking alternate ways to reach this population.

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The syntheses and spectra of some nickel(I1) perchlorate and chromium(II1) perchlorate complexes of a series of lactams of .C=O! general formula (H2CIn I oxygen-coordinated complexes.This order is compared to other data on ring size effects served for some fully substituted amides,2 is found to exist between the coordinated lactams. study confirm many of the conclusions drawn in the study of the amide complexes.are described. The ligand field parameters Dq and p are calculated for the octahedral, When R is hydrogen and n = 3, 4, or 5, the spectrochemical order toward nickel ( 11) is When R is methyl, a steric effect, previously obThe data obtained in this L -R -Introduction The donor properties of amides of general formula RC(0)NRz have been extensively studied. Invariably it has been found that oxygen is the principal donor site, and the oxygen is a better donor than is the carbonyl oxygen of acetone. This has been attributed3 to delocalization of the nonbonding electron pair on the nitrogen into a 7i.-molecular orbital involving oxygen, carbon, and nitrogen. The inductive effect of the R substituent in the amides is manifested by the following order of donor strengths toward phenol2: HC(0)-

By studying the ultraviolet spectra of mixtures of FeSfClOif (where S is the solvent) and (C2//5)42VC7 at different mole ratios, we have been able to determine the principal species present when a small amount of iron (III) chloride is dissolved in methanol, N-methylacetamide, or dimethyl sulfoxide. Dichloroand monochloroiron(III) complexes exist in methanol, monochloroiron(III) is the predominant species in dimethyl sulfoxide, and Fe-(CHiCONHCH^f* is formed in N-methylacetamide. These results are interpreted in terms of the donor strength and solvating ability of the solvent. Means of estimating these properties are discussed.

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