9781422279458

The periodic table is an ar- rangement of all the naturally occurring, and manufactured, elements known to humans at this point in time. An element is a substance that cannot be bro- ken down into simpler chem- ical substances. Ninety-two

To most people, gold is the most valuable and well-known element.

elements occur naturally on Earth and in space. Twenty-six more ele- ments (and counting) have been manufactured and analyzed in a lab- oratory setting. These elements, alone or in combination with others, form and shape all the matter around us. From the air we breathe, to the water we drink, to the bananas we eat—all these things are made of elements. These elements are organized into a chart called the periodic table. Since it was first developed in 1869, the periodic table went through several updates and reorganizations until it became the modern ver- sion of the table used today. On it, each square represents a single element. These elements are arranged into rows and columns by in- creasing atomic number. The atomic number equals the number of

The Chemistry of Everyday Elements

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