© Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. neutrons characteristicsof an element. orby chemical substances physical means. 2.1 Summa Chapter Name or moreor otheratoms. electrons,of theis number atom likely to a form are in chemically specific combined proportions. An a An element is that substance Metallic Covalent Ionic atoman When A withsame Atoms of the number smallestis An atom the • • • • • negative • • •

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with one atomic r essed ionic, Earth Science Guided Reading and Study Workbook ■ 15 Name Class Date

Chapter 2 Minerals 2.2 Minerals A mineral is a naturally occurring, inorganic solid with an orderly crystalline structure and a definite chemical composition. • Minerals form by natural processes. • Minerals are solids in normal temperature ranges on Earth. • Minerals are crystalline. Their atoms or ions are arranged in an orderly and repetitive way. • Minerals have definite chemical composition. They usually are compounds formed of two or more elements. • Most minerals are inorganic chemical compounds.

There are four major processes by which minerals form: crystallization from magma, precipitation, changes in pressure and temperature, and formation from hydrothermal solutions. • Magma is molten rock from deep in the Earth. As it cools, it forms minerals. (crystallization) • Substances dissolved in water may react to form minerals. (Precipitation) • Changes in temperature and pressure can make new minerals form. • When hot solutions touch existing minerals, chemical reactions take place and form new minerals. (hydrothermal) Common minerals, together with the thousands of others that form on

Earth, can be classified into groups based on their composition. ©

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Sulfates and sulfides are minerals that contain the element sulfur. Halides e

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Native elements are minerals that only contain one type of atom. Earth Science Guided Reading and Study Workbook ■ 16 © Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. even even surfaces. (softest). of arrangement atoms. mineral. di 2.3 2 Chapter Name to its volumeto its f ferent colorsferent Luster touseddescribe Luster is the Streak is diSmall amounts of Such as :______Such as other distinctive properties, minerals recognized Some beby such can is property Density a of that all ratioofmatter is the not saidthat broken Minerals show when do cleavage are to fracture. the Cleavage is The formCrystal theis • • • •

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mass Earth Science Guided Reading and Study Workbook ■ 17