9781422279496

element on the periodic table is unique, having its own chemical and physical properties. The periodic table also gives important informa- tion such as the number of protons and neutrons in the nucleus of one atom of an element, the number of electrons that surround the nucle- us, the atomic mass, and the general size of the atom. A symbol that is made up of one or two (or, in a few cases, three) letters represents the element. It is also possible to predict which state of matter—

solid, liquid, or gas—an element is most likely to be found based on its location. The periodic table is a very useful tool as one begins to investigate chemistry and science in general. This book is about the ele- ment silicon. Silicon is number 14 on the periodic table. Min- erals that contain the mineral silicon make up more than 90 percent of Earth’s crust. Silicon is therefore the second most

Count ’em up: This diagram shows the 14 electrons of a silicon atom.

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