Everyday things, chemistry

Relating the structures and chemistry of fats to everyday things as well as everyday chemical reactions. 

Compared with other subjects, chemistry is commonly believed to be more difficult, at least at the introductory level. There is some justification for this perception for one thing, chemistry has a very specialized vocabulary. However, even if this is your first course in chemistry, you already have more familiarity with the subject than you may realize. In everyday conversations we hear words that have a chemical connection, although they may not be used in the scientifically correct sense. Examples are electronic, quantum leap, equilibrium, catalyst, chain reaction, and critical mass. Moreover, if you cook, then you are a practicing chemist From experience gained in the kitchen, you know that oil and water do not mix and that boiling water left on the stove will evaporate. You apply chemical and physical principles when you use baking soda to leaven bread, choose a pressure cooker to shorten the time it takes to prepare soup, add meat tenderizer to a pot roast, squeeze lemon juice over sliced... 

Teachers and students often talk about relevance as a determinant of what interests them in their chemistry courses, and few people today would argue against the general principle of making chemistry - or any other subject -relevant. Osborne and Collins study of pupils and parents attitudes to science (2001) confirms what every teacher knows students like to relate chemical principles to everyday things. But how can this general principle be translated into practice ... 

Anyone who has sought in chemistry a road to the understanding of everyday things will probably have been impressed by the apparent gulf separating the substances with which simple chemical experiments are done in the laboratory and the materials of which the ordinary world seems largely to be made. Trees, rocks, aUoys, and many other common objects and substances are of evident complexity, and this is not aU even the simpler chemical bodies seem to be extraordinarily diverse, and the problem of their classification is a formidable one. Among the major questions of physical chemistry is that of the connexion between the electrical theory of matter, the kinetic theory, quantum mechanical and statistical principles, and the forms assumed by the various systems accessible to normal experience. 

Human development is clearly linked to continuous improvements in the materials used every day. Entire stages of history have been named after the critical materials—Stone Age, Bronze Age, Iron Age, and now, the Age of Plastics. When asked his opinion on chemistry s largest contribution to science and society, Lord Todd, the President of the Royal Society of London, responded I am inclined to think that the development of polymerization is, perhaps, the biggest thing chemistry has done, where it has had the biggest effect on everyday life. The world would be a totally different place without artificial fibers, plastics, elastomers, etc. (1). ... 

Yet another way to use this textbook is to use polymers as the examples for discussions or explanation of concepts covered in a chemistry course. Chapter 1 can be used in conjunction with the first chapter of any textbook where a discussion of What is chemistry occurs. A teacher wants students to know the importance of chemistry in their everyday lives and the good things that have been the result of chemistry, but it is also necessary to discuss some of the problems that have arisen because of the careless use of chemistry. (You can also refer to Chapter 9, Disposal, Degradation, And Recycling Bioplastics, for another angle on responsible chemistry.)... 

Abstract Chemistry is a central science because all the processes that sustain life are based on chemical reactions, and all things that we use in everyday life are natural or artificial chemical compounds. Chemistry is also a fantastic world populated by an unbelievable number of nanometric objects called molecules, the smallest entities that have distinct shapes, sizes, and properties. Molecules are the words of matter. Indeed, most of the other sciences have been permeated by the concepts of chemistry and the language of molecules. Like words, molecules contain specific pieces of information that are revealed when they interact with one another or when they are stimulated by photons or electrons. In the hands of chemists, molecules, particularly when they are suitably combined or assembled to create supramolecular systems, can play a variety of functions, even more complex and more clever than those invented by nature. The wonderful world of chemistry has inspired scientists not only to prepare new molecules or investigate new chemical processes, but also to create masterpieces. Some nice stories based on chemical concepts (1) show that there cannot be borders on the Earth, (2) underline that there is a tight connection among all forms of matter, and (3) emphasize the irreplaceable role of sunlight. 

Chemistry is inside and around us all the processes that sustain life are based on chemical reactions, and most things we use in everyday life are natural (e.g., water, wheat, oil, wood) or artificial (plastics, glass, medicines, pesticides) molecules. For these reasons Chemistry is a central science. Its importance and extension can be better perceived by a comparison with language. Molecules, the words of matter, are the smallest entities that have distinct shapes, sizes and properties. Like words, molecules contain specific pieces of information that are revealed when they interact with one another. 

The chemistry we use in our everyday life is generally beneficial to us for example, processed foods, medicines, pharmaceuticals, scents, detergents, fibres and fabrics, plastics, processed metals, paints and wall coverings, dyestuffs, fuels, bricks and ceramics, improved food production by the use of fertilisers and insecticides, and many more. Society often forgets all of these, and it has become a fashionable thing to blame the scientists for all the pollution in our world. But we, the consumers, decide what we want for a better lifestyle. We want more effective drugs, materials and food processing, etc., but all development requires expensive and tested research. 

A mixture is a combination of two or more pure substances in which each pure substance retains its individual chemical properties. The composition of mixtures is variable, and the number of mixtures that can be created by combining substances is infinite. Although much of the focus of chemistry is the behavior of substances, it is important to remember that most everyday matter occurs as mixtures. Substances tend naturally to mix it is difficult to keep things pure. 

Over the past weeks, you have seen numerous examples of how chemistry can deepen your understanding of everyday phenomena. In this chapter, we revisit the topic of liquids and the changes they undergo, in order to explain some of the things you might experience on an unusually warm spring morning. 

Explore today s world of chemistry. Learn how things work, discover chemistry in everyday experiences, uncover the links between chemistry and health, and investigate careers in chemistry. 

Chemistry and physics often deal with systems of a very different scale from the familiar everyday scale for which the system of SI units was developed the SI system is basically aimed at the human, engineering size of things while chemists may be dealing with tiny lengths and energies at the molecular level amd astronomers with vast distances and huge masses. 

What does being barefoot and pregnant on a cactus have to do with cherry ice cream You probably think that s a pretty bizarre question. But there is method to the madness. For over two decades now, I ve tried to answer the public s questions about everyday chemistry on the radio, I hope with some degree of success. Then, a few years ago, I had an idea. Why not spice things up by turning the situation around and asking my audience questions ... 

The first paragraphs in this chapter ask you if you have ever wondered how and why various things in our everyday lives happen the way they do. For your next class meeting, make a list of five similar chemistry-related things for discussion with your instructor and the other students in your class. 

For one thing, although chemistry imderpins materials science, chemistry itself is largely developed by the rather severe abstraction of being about substances. Very few everyday materials are pure samples of substances, and only a limited... 

John devoted considerable time and thought to teaching. He once said, I would throw away my notes after every lecture so that I wouldn t do the same thing the next year. I tried to talk about things that would interest students, to help them see the connection between chemistry and everyday life" (8). 

Lord Alexander Todd, the winner of the 1957 Nobel Prize in Chemistry, once stated that the development of polymerization was the biggest thing that chemistry has done, since this has had the biggest effect on everyday life. ... 

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