{"id":74,"date":"2018-03-19T15:26:38","date_gmt":"2018-03-19T15:26:38","guid":{"rendered":"https:\/\/courses.lumenlearning.com\/suny-orgbiochemistry\/chapter\/what-is-chemistry\/"},"modified":"2018-07-26T15:37:14","modified_gmt":"2018-07-26T15:37:14","slug":"what-is-chemistry","status":"publish","type":"chapter","link":"https:\/\/courses.lumenlearning.com\/suny-monroecc-orgbiochemistry\/chapter\/what-is-chemistry\/","title":{"raw":"1.1 What Is Chemistry?","rendered":"1.1 What Is Chemistry?"},"content":{"raw":"
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Learning Objectives<\/h3>\r\n
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  1. Define chemistry in relation to other sciences.<\/li>\r\n \t
  2. Identify the general steps in the scientific method.<\/li>\r\n<\/ol>\r\n<\/div>\r\n<\/div>\r\n \r\n

    Chemistry<\/strong> is the study of matter\u2014what it consists of, what its properties are, and how it changes. Being able to describe the ingredients in a cake and how they change when the cake is baked is called chemistry.\u00a0Matter<\/strong> is anything that has mass and takes up space\u2014that is, anything that is physically real. Some things are easily identified as matter\u2014this book, for example. Others are not so obvious. Because we move so easily through air, we sometimes forget that it, too, is matter.<\/p>\r\n

    Chemistry is one branch of science.\u00a0Science\u00a0<\/b><\/span>is the process by which we learn about the natural universe by observing, testing, and then generating models that explain our observations. Because the physical universe is so vast, there are many different branches of science (Figure 1.1<\/a>). Thus, chemistry is the study of matter, biology is the study of living things, and geology is the study of rocks and the earth. Mathematics is the language of science, and we will use it to communicate some of the ideas of chemistry.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"1151\"]\"image\" Figure 1.1 The Relationships between Some of the Major Branches of Science[\/caption]\r\n

    Although we divide science into different fields, there is much overlap among them. For example, some biologists and chemists work in both fields so much that their work is called biochemistry. Similarly, geology and chemistry overlap in the field called geochemistry. Figure 1.1<\/a>\u00a0shows how many of the individual fields of science are related.<\/p>\r\n\r\n

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    Chemistry lies more or less in the middle, which emphasizes its importance to many branches of science.<\/p>\r\n\r\n<\/div>\r\n

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    Note<\/h3>\r\n

    There are many other fields of science, in addition to the ones (biology, medicine, etc.) listed here.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n

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    Looking Closer: Alchemy<\/h3>\r\n

    As our understanding of the universe has changed over time, so has the practice of science. Chemistry in its modern form, based on principles that we consider valid today, was developed in the 1600s and 1700s. Before that, the study of matter was known as alchemy<\/em> and was practiced mainly in China, Arabia, Egypt, and Europe.<\/p>\r\n

    Alchemy was a somewhat mystical and secretive approach to learning how to manipulate matter. Practitioners, called alchemists, thought that all matter was composed of different proportions of the four basic elements\u2014fire, water, earth, and air\u2014and believed that if you changed the relative proportions of these elements in a substance, you could change the substance. The long-standing attempts to \u201ctransmute\u201d common metals into gold represented one goal of alchemy. Alchemy\u2019s other major goal was to synthesize the philosopher\u2019s stone, a material that could impart long life\u2014even immortality. Alchemists used symbols to represent substances, some of which are shown in the accompanying figure. This was not done to better communicate ideas, as chemists do today, but to maintain the secrecy of alchemical knowledge, keeping others from sharing in it.<\/p>\r\n

    In spite of this secrecy, in its time alchemy was respected as a serious, scholarly endeavor. Isaac Newton, the great mathematician and physicist, was also an alchemist.<\/p>\r\n\r\n<\/div>\r\n<\/div>\r\n

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    Example 1<\/h3>\r\n

    Which fields of study are branches of science? Explain.<\/p>\r\n\r\n

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    1. sculpture<\/li>\r\n \t
    2. astronomy<\/li>\r\n<\/ol>\r\n[reveal-answer q=\"305614\"]Show Answer[\/reveal-answer]\r\n[hidden-answer a=\"305614\"]Solution Sculpture is not considered a science because it is not a study of some aspect of the natural universe. Astronomy is the study of stars and planets, which are part of the natural universe. Astronomy is therefore a field of science.[\/hidden-answer]\r\n\r\n<\/div>\r\n
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      Skill-Building Exercise<\/h3>\r\nWhich fields of study are branches of science?\r\n
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      1. politics<\/li>\r\n \t
      2. physiology (the study of the function of an animal\u2019s or a plant\u2019s body)<\/li>\r\n \t
      3. geophysics<\/li>\r\n \t
      4. agriculture<\/li>\r\n<\/ol>\r\n<\/div>\r\n<\/div>\r\n<\/div>\r\n

        How do scientists work? Generally, they follow a process called the scientific method. The scientific method\u00a0<\/b><\/span>is an organized procedure for learning answers to questions. To find the answer to a question (for example, \u201cWhy do birds fly toward Earth\u2019s equator during the cold months?\u201d), a scientist goes through the following steps, which are also illustrated in <\/span>Figure 1.2.\u00a0<\/a><\/p>\r\n\r\n<\/div>\r\n

        \r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"955\"]\"image\" Figure 1.2 The General Steps of the Scientific Method[\/caption]\r\n

        The steps may not be as clear-cut in real life as described here, but most scientific work follows this general outline.<\/p>\r\n\r\n<\/div>\r\n

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        1. Propose a hypothesis.<\/strong> A scientist generates a testable idea, or hypothesis<\/span><\/strong>, to try to answer a question or explain how the natural universe works. Some people use the word theory in place of hypothesis, but the word hypothesis is the proper word in science. For scientific applications, the word theory<\/strong>\u00a0<\/span>is a general statement that describes a large set of observations and data. A theory represents the highest level of scientific understanding.<\/li>\r\n \t
        2. Test the hypothesis.<\/strong> A scientist evaluates the hypothesis by devising and carrying out experiments to test it. If the hypothesis passes the test, it may be a proper answer to the question. If the hypothesis does not pass the test, it may not be a good answer.<\/li>\r\n \t
        3. Refine the hypothesis if necessary.<\/strong> Depending on the results of experiments, a scientist may want to modify the hypothesis and then test it again. Sometimes the results show the original hypothesis to be completely wrong, in which case a scientist will have to devise a new hypothesis.<\/li>\r\n<\/ol>\r\n

          Not all scientific investigations are simple enough to be separated into these three discrete steps. But these steps represent the general method by which scientists learn about our natural universe.<\/p>\r\nThe knowledge gained through scientific inquiry is often summarized in one of three ways:\r\n

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          1. Scientific Law.\u00a0 <\/strong>A scientific law, often summarized by a mathematical equation, describes a phenomenon that has been reliably observed many times and thus can be used to predict results.\u00a0 An example is using the law of conservation of mass, which states that mass is not created or destroyed in chemical reactions,\u00a0 to predict the amount of products based on the amount of reactants used.<\/li>\r\n \t
          2. Scientific Theory. <\/strong>A scientific theory, often summarized by several statements, explains what underlies scientific laws.\u00a0 For example, one point of atomic theory is that matter is made up of small discrete particles that maintain their identities as they undergo chemical changes, and this underlies that law of conservation of mass.<\/li>\r\n \t
          3. Scientific Model. <\/strong> Many scientific phenomena are too small, too large, or too complicated to observe directly, so scientists use physical, computer-based, and mathematical models to summarize their ideas and to allow further testing.\u00a0 For example, we cannot see molecules, but we can build physical or virtual models of molecules in order to evaluate properties such as shape and polarity.<\/li>\r\n<\/ol>\r\n \r\n
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            Concept Review Exercises<\/h3>\r\n
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              Define science<\/em> and chemistry<\/em>.<\/p>\r\n\r\n<\/div><\/li>\r\n \t

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              Name the steps of the scientific method.<\/p>\r\n

              [reveal-answer q=\"589291\"]Show Answer[\/reveal-answer]\r\n[hidden-answer a=\"589291\"]Science is a process by which we learn about the natural universe by observing, testing, and then generating models that explain our observations. Chemistry is the study of matter. propose a hypothesis, test the hypothesis, and refine the hypothesis if necessary[\/hidden-answer]<\/p>\r\n\r\n<\/div><\/li>\r\n<\/ol>\r\n<\/div>\r\n

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              Key Takeaways<\/h3>\r\n