Chemical Engineering License Review, Second Edition
This text contains 146 problems with detailed step-by-step solutions, and is an ideal study guide and the first truly practical, no-nonsense review for the difficult PE Exam.
TABLE OF CONTENTS Chemical Engineering License Review, Second Edition
Chapter 1: Units and Dimensions
With the adoption of the International System of Units (SI units) as the standard by most nations, including the United States and United Kingdom, there has been a progressively greater emphasis on the use of SI units. Besides knowing the customary fps (engineering) and cgs units, candidates for the P.E. examination should familiarize themselves with the SI units. The following discussion provides a short review of the different systems of units and their conversions into one another.
Dimensions
A physical quantity consists of two parts: (1) a unit which indicates the dimension and gives its standard of measurement and (2) a quantity which gives the numerical value of the units. For example, the distance between two points has the dimension of length and can be expressed as 3 feet. Here the foot is the unit of the length dimension, and 3 is the numerical value of the corresponding number of length units.
Physical properties of a system are interrelated by mechanical and physical laws. Such relationships allow certain dimensions to be regarded as basic and others as derived. The dimensions chosen as basic vary from one system to another, but it is usual to treat length L, time T, and mass M as basic. In some systems, force F or both mass M and force F are used as the basic dimensions.
Systems of Units
The systems of units which chemical engineers are usually required to use in their work are described next.
Centimeter-Gram-Second...
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