Some Fundamental Chemical Concepts

We begin the study of physical chemistry with a brief statement of a few fundamental ideas and common usages in chemistry. These are very familiar things, but it is worth while recalling them to mind. 

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All drugs are chemicals, and pharmacy is a subject that deals with the study of various aspects of drugs. Therefore, it is needless to say that to become a good pharmacist the knowledge of the chemistry of drugs is essential. Before moving on to the other chapters, let us try to understand some of the fundamental chemical concepts in relation to the physical properties of drug molecules. 

The concept of pH is one of the most fundamental in chemistry, but has a broad significance in many other disciplines such as biochemistry, biology, physics, medicine, agriculture, environmental pollution, and is important in numerous practical fields, especially in chemical industry, environmental protection, food production, and others. This article discusses the basic definitions of pH, its effect on some fundamental chemical reactions of importance in analytical chemistry. Although the concept of pH is mainly used for aqueous solutions its extension to other solvents is mentioned, as well as the main methods of pH evaluation. 

Some of the concepts that chemists have introduced for the discussion of chemical reactivity are summarized below. Much of this will be common knowledge to readers that have studied chemistry they can easily skip this section. However, for readers from other scientific disciplines or whose chemical knowledge has become rusty, some fundamental concepts are presented here. 

We discussed mainly some of the possible applications of Fukui function and local softness in this chapter, and described some practical protocols one needs to follow when applying these parameters to a particular problem. We have avoided the deeper but related discussion about the theoretical development for DFT-based descriptors in recent years. Fukui function and chemical hardness can rigorously be defined through the fundamental variational principle of DFT [37,38]. In this section, we wish to briefly mention some related reactivity concepts, known as electrophilicity index (W), spin-philicity, and spin-donicity. 

In this project students review the Chapman cycle mechanism in detail and some photochemistry concepts including the photostationary state. A key element of this project is its focus on an important chemical mechanism and the use of exploratory options for predicting ozone concentrations as a function of time while reviewing other fundamental chemical kinetics concepts. Mathcad is used as the symbolic mathematics engine for solving the requisite differential equations and ample instruction is provided to students to guide them on the use of the software in this project. 

These and other experiments led Langmuir to develop some fundamental concepts on adsorption. One of these is that the forces involved in adsorption are just as large as those in chemical compounds. These forces are usually short-range forces. If the adatom is removed from the surface... 

In this chapter, we discuss the fundamental principles of chemical reactivity and catalysis to understand the organic chemistry of catalysis and how to analyze it. We begin with transition state theory because it provides a simple framework for understanding much about reactivity and kinetics. We progress to structure-activity relationships and also discuss some fundamental concepts in analyzing mechanisms. 

In this chapter we have presented some fundamental concepts of distillation control. Distillation columns are without question the most widely used unit operation for separation in the chemical industry. Most final products are produced from one end or the other of a distillation column, so tight control of product quality requires an effective control system for the column. However, the column is usually an integral part of an entire plant, so its control scheme must also be consistent with the plantwide control structure. 

Some of these concepts are illustrated in the skeletal structure for capsaicin. As we continue our study of organic chemistry you will see that these fundamental properties about a molecule determine its physical properties and its behavior in chemical reactions. 

The molecular orbital (MO) is the fundamental quantity in contemporary quantum chemistry. Almost all of our understanding of what the electrons are doing in molecules is based on the molecular orbital concept. Also, most of the computational methods used today start by a calculation of the molecular orbitals of the system using some quantum chemical method. 

First, some fundamental concepts of thermodynamics are introduced and these will be discussed in greater detail in subsequent sections. In this Appendix we treat phenomena relevant to mechanics and temperature other effects including chemical fields (cf. Appendix E) and electromagnetic effects are excluded. Further expositions are given by de Groot and Mazur (1962), Kestin (1979) and Kondepudi and Prigogine (1998). 

Heat balance calculations are usually carried out when developing new rotary kiln chemical processes or when improving old ones. No thermal process would work if too much heat is released or if there is a lack of sufficient thermal energy to drive the process, in other words, to maintain the reaction temperature. Heat balance can only be calculated with given mass balances as the boundary conditions, hence a quantitative description of the chemical processes on the basis of physical or chemical thermodynamics is required. While chemical thermodynamics establishes the feasibility of a particular reaction under certain reactor conditions, chemical kinetics determines the rate at which the reaction will proceed. Before we establish the global rotary kiln mass and energy balance, it is important to examine some fundamental concepts of thermodynamics that provide the pertinent definitions essential for the design of new rotary kiln bed processes. 

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