Structure and Composition of Elements

At the end of Section 1.3.2, we indicated that composition and structure aspects of chemistry are at the heart of the concept of chemical combination. Let us now begin to explore the meaning of chemical combination by looking more closely at the structure and composition of elements and compounds. 

with the help of a chemist friend, you gain access to the most powerful microscope in the world, and you continue the cutting and discarding process. Finally, you get to the point at which you can absolutely go no further. At that point, you have a speck of silver barely visible through this most powerful microscope. The question in your mind is, how far would I be able to go if I could go farther And so you start to dream and imagine that you have access to a microscope so powerful that you can see the tiniest objects that can possibly exist. 

Then you resume the cutting and discarding process and you finally reach the smallest particle of silver that you can have, such that if you proceed further to divide this smallest particle, you discover that it is no longer silver. The question is, what is this smallest possible particle The smallest particle of an element that can exist and still be that element is called an atom of that element. The atom is the most fundamental structural unit of all of matter, the 

FIGURE 1.3 Looking at a sample of an element through a powerful microscope that can only be imagined, scientists believe we would see a stack of spheres that are the atoms of that element. Microscope image from Shutterstock.com. 

The utterly small sizes of all atoms, however, caimot be overemphasized. In spite of the fact that francium atoms are relatively large, it would take hundreds of thousands of them, lined up side by side, to make a line visible to the naked eye. 

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