Feature Problem

574 g sample of CUSO4 x H2O was heated to 140 °C, cooled, and reweighed. The resulting solid was reheated to 400 °C, cooled, and reweighed. Finally, this solid was heated to 1000 °C, cooled, and reweighed for the last time. 

Some substances that are only very slightly soluble in water will spread over the surface of water to produce a film that is called a monolayer because it is only one molecule thick. A practical use of this phenomenon is to cover ponds to reduce the loss of water by evaporation. Stearic acid forms a monolayer on water. The molecules are arranged upright and in contact with one another, rather like pencils tightly packed and standing upright in a coffee mug. The model below represents an individual stearic acid molecule in the monolayer. 

10 mL sample of solution (4) is spread in a mono-layer on water. The area covered by the monolayer is 85 cm. Assume that oleic acid molecules are arranged in the same way as described for stearic acid, and that the cross-sectional area of the molecule is 4.6 X 10 cm. The density of oleic acid is 0.895 g/mL. Use these data to obtain an approximate value of Avogadro s number. 

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Gandhi, S., and Bhat, I., Organometallic Vapor Phase Epitaxy Features, Problems New Approaches, MRS Bulletin, pp. 39-43 (Nov. 1988)... 

Plot slope = constant from Feature Problem 110... 

Draw structures using any of the methods we have seen. You should also be able to examine a shorthand representation for a molecule and recognize all of its features. (Problems 2.17 and 2.18)... 

Discuss the structure and stereochemistry of polymers in terms of both regular and irregular features. (Problems 24.24 and 24.35)... 

All chapters contain exercises of four types questions, problems, points to ponder, and feature problems and projects. The questions ask the student to recall many of the key concepts from the chapter. The problems ask the student to apply what they have learned to solve problems similar to those in the chapter Examples and Your Turn boxes. The points to ponder consist primarily of open-ended short-essay questions in which students are asked about the ethical, societal, and political implications of scientific issues. The feature problems and projects contain problems with graphics and short projects, often involving web-based inquiry. 

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