560 likes | 681 Views
2.0 Rocks and Minerals!. A Review of Chemistry!. An atom is the smallest particle of matter that contains the characteristics of an element . . Elements and the Periodic Table. 2.1 Matter. Elements are the b asic building blocks of minerals .
E N D
A Review of Chemistry! • An atom is the smallest particle of matter that contains the characteristics of an element.
Elements and the Periodic Table 2.1 Matter • Elementsare the basic building blocks of minerals. • An element is a substance that cannot be broken down into simpler substances by chemical or physical means. Over 100 elements are known.
Elements • An element is a chemical made of all the same type of atoms. • Types of elements (most common in the Earth’s crust) • Oxygen (O) • Silicon (Si) • Aluminum (Al) • Iron (Fe) • Calcium (Ca) • Sodium (Na) • Potassium (K) • Magnesium (Mg)
Words that Matter… • A substance is a material with a specific chemical composition. • A compound is a pure chemical substance consisting of two or more different chemical substances. • A mixture is a collection of molecules or atoms of different types.
Minerals • A mineral is a naturally occurring, inorganicsolid with an orderly crystalline structure and definite chemical composition. • Say what??????????????
Let’s Break it Down! • Let’s look at each part of the definition in detail! A mineral is a naturally occurring, inorganicsolid with an orderly crystalline structure and definite chemical composition.
A mineral is a naturally occurring, inorganicsolid with an orderly crystalline structure and definite chemical composition. • Naturally occurring means that the mineral was made by natural geologic processes over time. Minerals cannot be made by humans!
A mineral is a naturally occurring, inorganicsolid with an orderly crystalline structure and definite chemical composition. • Inorganic means that it does not contain carbon. • There are a few exceptions such as calcium carbonate (limestone).
Peat (partially decomposed organic material) is not a mineral because it is not inorganic=organic!
A mineral is a naturally occurring, inorganicsolidwith an orderly crystalline structure and definite chemical composition. • Solid means that the minerals are solid within normal temperatures on the Earth! • Of course, they can be melted or turned into a liquid if heated up high enough!
A mineral is a naturally occurring, inorganicsolid with an orderly crystalline structureand definite chemical composition. • Orderly crystalline structure means that the atoms are arranged in an orderly and repetitive manner. There are a few exceptions to this.
Obsidian (volcanic glass) is sometimes not considered a mineral because glass is not a crystal!
A mineral is a naturally occurring, inorganicsolid with an orderly crystalline structure and definite chemical composition. • Definite chemical composition means that the minerals are composed of elements that occur in a consistent ratio.
2.2Minerals Summary 1. Naturally occurring 2. Solid substance 3. Orderly crystalline structure 4. Definite chemical composition 5. Generally considered inorganic
2.2Mineral Formation • How Are Minerals Formed???
2.2Mineral Formation • Minerals form almost everywhere in the Crust under different conditions. • Some minerals form deep within the Crust and others are formed in shallow deposits. • Some minerals form in ocean water and some are made from other minerals that have been crushed and compressed.
2.2Mineral Formation • There are four major processes by which minerals are formed: • Crystallization from magma • Precipitation • Changes in pressure and temperature • Formation from hydrothermal solutions.
2.2Mineral Formation: Crystalization Crystallization from Magma • As magma (molten rock) cools, the elements chemically combine to form minerals. • Usually the iron, calcium and magnesium minerals crystallize first. The sodium, potassium and aluminum minerals will crystallize next.
2.2Mineral Formation: Crystalization When the magma cools, the crystals form.
2.2Mineral Formation: Precipitation Precipitation • The water found in oceans, lakes, streams, and rivers contain dissolved substances in it. When the water evaporates, some of the dissolved substances in the water can crystalize to form minerals.
2.2Mineral Formation: Precipitation • Limestone and halite (sodium chloride) are two minerals formed by precipitation.
2.2Mineral Formation: Pressure/Temp Pressure and Temperature • When existing minerals are subjected to extreme (high) pressure and temperatures, new minerals can form. Marble
2.2Mineral Formation: Hydrothermal Hydrothermal Solution • A hydrothermal solution is a very hot (between 100⁰ C and 300 ⁰ C) mixture of water and dissolved substances. • When the solution cools, chemical reactions can take place to form new minerals.
2.2Mineral Groups • Over 3,800 different types of minerals have been identified and named! • These minerals are classified based on their composition. • The major classes of minerals on earth are: • Silicates, carbonates, oxides, sulfates/sulfides, halides, and native elements. • Can you guess what element each of these groups contain?
2.2 Mineral Groups: Silicates Silicates • Silicates are the most abundant mineral on Earth! • They contain what two elements? • Yes! They contain oxygen and silicon (usually with other elements too!)
2.2Mineral Groups: Silicates • Silicates are made from cooling magma and can occur on the Earth’s surface or deep within the crust.
2.2 Mineral Groups: Silicates Examples of Silicates • Clay and Sand • Quartz • Mica • Feldspar
2.2 Mineral Groups: Silicates Quartz Often Exhibits Good Crystal Form.
2.2 Mineral Groups: Carbonates Carbonates! • Carbonates are the second most common group of minerals. • Carbonates contain carbon, oxygen (CO32-)and one or more other metallic element.
2.2 Mineral Groups: Carbonates Examples of Carbonates • Calcium carbonate (limestone and marble) • Dolomite • Calcite (most common carbonate)
2.2 Mineral Groups: Oxides Oxides • Oxides are minerals which contain oxygen plus one or more other elements (often a metal like iron or copper). • Oxides can be made on the Earth’s surface or deep within the crust. • Oxides often have the name of the metal and then the word oxide such as iron oxide (Fe2O3), copper oxide (CuO2), or aluminum oxide (Al2O3).
Examples! • Copper Oxide • Iron Oxide
2.2 Mineral Groups: Sulfates-ides Sulfates and Sulfides • Sulfates and Sulfides contain the element sulfur FeS2 (pyrite=fools gold)
2.2 Mineral Groups: Sulfates-ides Gypsum (sulfate) CaSO4 . 2H2O
2.2 Mineral Groups: Halides Halides • Halides are minerals that contain a halogen (fluorine, chlorine, bromine or iodine) plus one or more other elements. NaCl
2.2 Mineral Groups: Native Elements • Native elements are minerals of a single element such as gold, platinum, silver, carbon