Submicroscopic realm

In this chapter we explored many of the rudiments of chemistry, including how matter is described by its physical and chemical properties and denoted by elemental and chemical formulas. We saw how compounds are different from the elements from which they are formed and how mixtures can be separated by taking advantage of differences in the physical properties of the components. Also addressed was what a chemist means by pure and how matter can be classified as element, compound, or mixture. Lastly, we saw how elements are organized in the periodic table by their physical and chemical properties. /Jong the way, you were introduced to some of the most important key terms of chemistry. With an understanding of these fundamental concepts and of the language used to describe them, you are well equipped to continue your study of nature s submicroscopic realm. 

Every change in the observable world—from boiling water to the changes that occur as our bodies combat invading viruses—has its basis in the world of atoms and molecules. Thus, as we proceed with our study of chemistry, we will find ourselves thinking in two realms the macroscopic realm of ordinary-sized objects macro = large) and the submicroscopic realm of atoms and molecules. We make our observations in the macroscopic world, but in order to understand that world, we must visualize how atoms and molecules behave at the submicroscopic level. Chemistry is the science that seeks to understand the properties and behavior of matter by studying the properties and behavior of atoms and molecules. 

Our world can be studied at different levels of magnification. At the macroscopic level, matter is large enough to be seen, measured, and handled. A handful of sand and a glass of water are macroscopic samples of matter. At the micro-scopic level, physical structure is so fine that it can be seen only with a microscope. A biological cell is microscopic, as is the detail on a dragonfly s wing. Beyond the microscopic level is the submicroscopic—the realm of atoms and molecules and an important focus of chemistry. 

Submicroscopic The realm of atoms and molecules, where objects are smaller than can be detected by optical microscopes. 

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