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General Chemistry Principles, Patterns, and Applications, 2011

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c. Using the Clausius–Clapeyron equation, show why it is possible to remove water <strong>and</strong> still<br />

maintain a low temperature at this pressure.<br />

5. ♦ Many industrial processes for preparing compounds use “continuous-flow reactors,” which are chemical<br />

reaction vessels in which the reactants are mixed <strong>and</strong> allowed to react as they flow along a tube. The<br />

products are removed at a certain distance from the starting point, when the reaction is nearly complete. The<br />

key operating parameters in a continuous-flow reactor are temperature, reactor volume, <strong>and</strong> reactant flow<br />

rate. As an industrial chemist, you think you have successfully modified a particular process to produce a<br />

higher product yield by substituting one reactant for another. The viscosity of the new reactant is, however,<br />

greater than that of the initial reactant.<br />

a. Which of the operating parameters will be most greatly affected by this change?<br />

b. What other parameter could be changed to compensate for the substitution?<br />

c. Predict the possible effects on your reactor <strong>and</strong> your process if you do not compensate for<br />

the substitution.<br />

Chapter 12<br />

Solids<br />

In this chapter, we turn our attention to the structures <strong>and</strong> properties of solids. The solid state is distinguished from<br />

the gas <strong>and</strong> liquid states by a rigid structure in which the component atoms, ions, or molecules are usually locked into<br />

place. In many solids, the components are arranged in extended three-dimensional patterns, producing a wide range<br />

of properties that can often be tailored to specific functions. Thus diamond, an allotrope of elemental carbon, is one of<br />

the hardest materials known, yet graphite, another allotrope of carbon, is a soft, slippery material used in pencil lead<br />

<strong>and</strong> as a lubricant. Metallic sodium is soft enough to be cut with a dull knife, but crystalline sodium chloride turns<br />

into a fine powder when struck with a hammer.<br />

Solids, also called materials, are so important in today’s technology that the subdisciplines of solid-state chemistry<br />

<strong>and</strong> materials science are among the most active <strong>and</strong> exciting areas of modern chemical research. After presenting a<br />

basic survey of the structures of solids, we will examine how the properties of solids are determined by their<br />

composition <strong>and</strong> structure. We will also explore the principles underlying the electrical properties of metals,<br />

insulators, semiconductors (which are at the heart of the modern electronics industry), <strong>and</strong> superconductors. By the<br />

end of the chapter, you will know why some metals “remember” their shape after being bent <strong>and</strong> why ceramics are<br />

used in jet engines. You will also underst<strong>and</strong> why carbon- or boron-fiber materials are used in high-performance golf<br />

Saylor URL: http://www.saylor.org/books<br />

Saylor.org<br />

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