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60-507: Hainich is 18,6 mls (30 km) long from north to south and 2,5 to 5 mls (4 to 8 km) broad from west to east. The western edge of Hainich leads to Lempertsbach and Lauterbach valley and is steeper than the eastern slope. In the northwest you can find high rocks like Sommerstein and Winterstein . The reason for the steeper slopes in western Hainich is the Saalfeld-Gotha-Eichenberg fault . Because of limestone

120-424: A chemical compound ; the concept is most readily understood when considering pure chemical substances . It follows from their being composed of fixed proportions of two or more types of atoms that chemical compounds can be converted, via chemical reaction , into compounds or substances each having fewer atoms. A chemical formula is a way of expressing information about the proportions of atoms that constitute

180-550: A chemical reaction , which may involve interactions with other substances. In this process, bonds between atoms may be broken and/or new bonds formed. There are four major types of compounds, distinguished by how the constituent atoms are bonded together. Molecular compounds are held together by covalent bonds ; ionic compounds are held together by ionic bonds ; intermetallic compounds are held together by metallic bonds ; coordination complexes are held together by coordinate covalent bonds . Non-stoichiometric compounds form

240-420: A laboratory or factory . Mining in a wider sense comprises extraction of any resource (e.g. petroleum , natural gas , salt or even water ) from the earth. Mining of rock and metals has been done since prehistoric times. Modern mining processes involve prospecting for mineral deposits, analysis of the profit potential of a proposed mine, extraction of the desired materials, and finally reclamation of

300-419: A solid-state reaction , or the electron transfer reaction of reactive metals with reactive non-metals, such as halogen gases. Ionic compounds typically have high melting and boiling points , and are hard and brittle . As solids they are almost always electrically insulating , but when melted or dissolved they become highly conductive , because the ions are mobilized. An intermetallic compound

360-681: A broadleaf forest. An attraction in Mühlhäuser Stadtwald are the Redwood trees ( Sequoiadendron giganteum ) from 1884. They are the largest ones in Thuringia. A trail from Weißes Haus on the eastern edge of Hainich leads to this site. Another curious tree, also in Mühlhäuser Stadtwald , is Corpusbuche a 400-year-old hornbeam. 51°06′N 10°23′E  /  51.100°N 10.383°E  / 51.100; 10.383 Rock (geology) In geology , rock (or stone )

420-412: A continuous three-dimensional network, usually in a crystalline structure . Ionic compounds containing basic ions hydroxide (OH ) or oxide (O ) are classified as bases. Ionic compounds without these ions are also known as salts and can be formed by acid–base reactions . Ionic compounds can also be produced from their constituent ions by evaporation of their solvent , precipitation , freezing ,

480-527: A disputed marginal case. A chemical formula specifies the number of atoms of each element in a compound molecule, using the standard chemical symbols with numerical subscripts . Many chemical compounds have a unique CAS number identifier assigned by the Chemical Abstracts Service . Globally, more than 350,000 chemical compounds (including mixtures of chemicals) have been registered for production and use. The term "compound"—with

540-402: A fourth class of rocks alongside igneous, sedimentary, and metamorphic. Rock varies greatly in strength, from quartzites having a tensile strength in excess of 300 MPa to sedimentary rock so soft it can be crumbled with bare fingers (that is, it is friable ). (For comparison, structural steel has a tensile strength of around 350 MPa. ) Relatively soft, easily worked sedimentary rock

600-433: A huge impact on the cultural and technological development of the human race. Rock has been used by humans and other hominids for at least 2.5 million years . Lithic technology marks some of the oldest and continuously used technologies. The mining of rock for its metal content has been one of the most important factors of human advancement, and has progressed at different rates in different places, in part because of

660-444: A meaning similar to the modern—has been used at least since 1661 when Robert Boyle's The Sceptical Chymist was published. In this book, Boyle variously used the terms "compound", "compounded body", "perfectly mixt body", and "concrete". "Perfectly mixt bodies" included for example gold, lead, mercury, and wine. While the distinction between compound and mixture is not so clear, the distinction between element and compound

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720-566: A particular chemical compound, using chemical symbols for the chemical elements, and subscripts to indicate the number of atoms involved. For example, water is composed of two hydrogen atoms bonded to one oxygen atom: the chemical formula is H 2 O. In the case of non-stoichiometric compounds , the proportions may be reproducible with regard to their preparation, and give fixed proportions of their component elements, but proportions that are not integral [e.g., for palladium hydride , PdH x (0.02 < x < 0.58)]. Chemical compounds have

780-496: A positively charged cation . The nonmetal will gain the electrons from the metal, making the nonmetal a negatively charged anion . As outlined, ionic bonds occur between an electron donor, usually a metal, and an electron acceptor, which tends to be a nonmetal. Hydrogen bonding occurs when a hydrogen atom bonded to an electronegative atom forms an electrostatic connection with another electronegative atom through interacting dipoles or charges. A compound can be converted to

840-447: A solid state dependent on how low the temperature of the environment is. A covalent bond , also known as a molecular bond, involves the sharing of electrons between two atoms. Primarily, this type of bond occurs between elements that fall close to each other on the periodic table of elements , yet it is observed between some metals and nonmetals. This is due to the mechanism of this type of bond. Elements that fall close to each other on

900-562: A source area and then transported to the place of deposition by water , wind , ice , mass movement or glaciers (agents of denudation ). About 7.9% of the crust by volume is composed of sedimentary rocks, with 82% of those being shales, while the remainder consists of 6% limestone and 12% sandstone and arkoses . Sedimentary rocks often contain fossils . Sedimentary rocks form under the influence of gravity and typically are deposited in horizontal or near horizontal layers or strata , and may be referred to as stratified rocks. Sediment and

960-713: A texture are referred to as foliated ; the remainders are termed non-foliated. The name of the rock is then determined based on the types of minerals present. Schists are foliated rocks that are primarily composed of lamellar minerals such as micas . A gneiss has visible bands of differing lightness , with a common example being the granite gneiss. Other varieties of foliated rock include slates , phyllites , and mylonite . Familiar examples of non-foliated metamorphic rocks include marble , soapstone , and serpentine . This branch contains quartzite —a metamorphosed form of sandstone —and hornfels . Though most understanding of rocks comes from those of Earth, rocks make up many of

1020-469: A unique and defined chemical structure held together in a defined spatial arrangement by chemical bonds . Chemical compounds can be molecular compounds held together by covalent bonds , salts held together by ionic bonds , intermetallic compounds held together by metallic bonds , or the subset of chemical complexes that are held together by coordinate covalent bonds . Pure chemical elements are generally not considered chemical compounds, failing

1080-400: Is 19,5 mls (31,3 km) long and leads from Eigenrieden in the north to Behringen in the south across Hainich. On 26 August 2005 nearby Thiemsburg forester's house in the southeast of Hainich one of the largest tree canopy paths was declared to be open. It is the most important institution for environmental education in Thuringia and a platform for ecological research in the treetop region of

1140-565: Is Middle Triassic limestone so called Muschelkalk . The annual average precipitation at Hainich ridge is as 31.5 in (800 mm). The average temperature is 43,7 °F (6,5 °C). The lower parts in the east are drier and warmer. The next commercial weather station is near Weberstedt . Hainich contains the largest coherent area of deciduous trees in Germany. The main trees are beech , mixed with ash , maple , tilia cordata , hornbeam and chequer tree ( Sorbus torminalis ). Hainich

1200-445: Is a central theme. Quicksilver ... with Aqua fortis will be brought into a ... white Powder ... with Sulphur it will compose a blood-red and volatile Cinaber. And yet out of all these exotick Compounds, we may recover the very same running Mercury. Boyle used the concept of "corpuscles"—or "atomes", as he also called them—to explain how a limited number of elements could combine into a vast number of compounds: If we assigne to

1260-403: Is a type of metallic alloy that forms an ordered solid-state compound between two or more metallic elements. Intermetallics are generally hard and brittle, with good high-temperature mechanical properties. They can be classified as stoichiometric or nonstoichiometric intermetallic compounds. A coordination complex consists of a central atom or ion, which is usually metallic and is called

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1320-477: Is also known as an important habitat for European wildcat ( Felis silvestris ). Central parts of Hainich National Park, so Weberstedt and Schöndorf forest, are rich on dead wood . That's the reason for the incidence of 522 beetles with their habitat only in wood. Biologists found from 1992 to 2008 altogether 2080 of different beetles in Hainich National Park. The north of Hainich is managed by

1380-608: Is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its chemical composition , and the way in which it is formed. Rocks form the Earth's outer solid layer, the crust , and most of its interior, except for the liquid outer core and pockets of magma in the asthenosphere . The study of rocks involves multiple subdisciplines of geology, including petrology and mineralogy . It may be limited to rocks found on Earth, or it may include planetary geology that studies

1440-458: Is formed through the cooling and solidification of magma or lava . This magma may be derived from partial melts of pre-existing rocks in either a planet 's mantle or crust . Typically, the melting of rocks is caused by one or more of three processes: an increase in temperature, a decrease in pressure, or a change in composition. Igneous rocks are divided into two main categories: Magmas tend to become richer in silica as they rise towards

1500-493: Is neutral overall, but consists of positively charged ions called cations and negatively charged ions called anions . These can be simple ions such as the sodium (Na ) and chloride (Cl ) in sodium chloride , or polyatomic species such as the ammonium ( NH 4 ) and carbonate ( CO 3 ) ions in ammonium carbonate . Individual ions within an ionic compound usually have multiple nearest neighbours, so are not considered to be part of molecules, but instead part of

1560-442: Is next in importance. About 65% of the Earth's crust by volume consists of igneous rocks. Of these, 66% are basalt and gabbro , 16% are granite, and 17% granodiorite and diorite . Only 0.6% are syenite and 0.3% are ultramafic . The oceanic crust is 99% basalt, which is an igneous rock of mafic composition. Granite and similar rocks, known as granitoids , dominate the continental crust . Sedimentary rocks are formed at

1620-453: Is the study of Earth and its components, including the study of rock formations. Petrology is the study of the character and origin of rocks. Mineralogy is the study of the mineral components that create rocks. The study of rocks and their components has contributed to the geological understanding of Earth's history, the archaeological understanding of human history, and the development of engineering and technology in human society. While

1680-452: The coordination centre , and a surrounding array of bound molecules or ions, that are in turn known as ligands or complexing agents. Many metal-containing compounds, especially those of transition metals , are coordination complexes. A coordination complex whose centre is a metal atom is called a metal complex of d block element. Compounds are held together through a variety of different types of bonding and forces. The differences in

1740-417: The history of geology includes many theories of rocks and their origins that have persisted throughout human history, the study of rocks was developed as a formal science during the 19th century. Plutonism was developed as a theory during this time, and the discovery of radioactive decay in 1896 allowed for the radiocarbon dating of rocks. Understanding of plate tectonics developed in the second half of

1800-449: The oxygen molecule (O 2 ); or it may be heteronuclear , a chemical compound composed of more than one element, as with water (two hydrogen atoms and one oxygen atom; H 2 O). A molecule is the smallest unit of a substance that still carries all the physical and chemical properties of that substance. An ionic compound is a chemical compound composed of ions held together by electrostatic forces termed ionic bonding . The compound

1860-399: The 20th century. Rocks are composed primarily of grains of minerals, which are crystalline solids formed from atoms chemically bonded into an orderly structure. Some rocks also contain mineraloids , which are rigid, mineral-like substances, such as volcanic glass , that lack crystalline structure. The types and abundance of minerals in a rock are determined by the manner in which it

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1920-907: The Corpuscles, whereof each Element consists, a peculiar size and shape ... such ... Corpuscles may be mingled in such various Proportions, and ... connected so many ... wayes, that an almost incredible number of ... Concretes may be compos’d of them. In his Logick , published in 1724, the English minister and logician Isaac Watts gave an early definition of chemical element, and contrasted element with chemical compound in clear, modern terms. Among Substances, some are called Simple, some are Compound ... Simple Substances ... are usually called Elements, of which all other Bodies are compounded: Elements are such Substances as cannot be resolved, or reduced, into two or more Substances of different Kinds. ... Followers of Aristotle made Fire, Air, Earth and Water to be

1980-467: The Earth's surface, a process called magma differentiation . This occurs both because minerals low in silica crystallize out of the magma as it begins to cool ( Bowen's reaction series ) and because the magma assimilates some of the crustal rock through which it ascends ( country rock ), and crustal rock tends to be high in silica. Silica content is thus the most important chemical criterion for classifying igneous rock. The content of alkali metal oxides

2040-503: The Earth's surface: temperatures greater than 150 to 200 °C and pressures greater than 1500 bars. This occurs, for example, when continental plates collide. Metamorphic rocks compose 27.4% of the crust by volume. The three major classes of metamorphic rock are based upon the formation mechanism. An intrusion of magma that heats the surrounding rock causes contact metamorphism—a temperature-dominated transformation. Pressure metamorphism occurs when sediments are buried deep under

2100-411: The Earth. Other compounds regarded as chemically identical may have varying amounts of heavy or light isotopes of the constituent elements, which changes the ratio of elements by mass slightly. A molecule is an electrically neutral group of two or more atoms held together by chemical bonds. A molecule may be homonuclear , that is, it consists of atoms of one chemical element, as with two atoms in

2160-614: The Hainich creeks are dry for the most time of the year. In the east of Hainich water rises up in strong sources like Kainspring or Popperöder Quelle . So Hainich is a karst region. The following communities take part of Hainich: Eigenrieden, Heyerode , Hallungen , Nazza , Mihla , Lauterbach , Bischofroda , Berka v.d Hainich, Behringen , Reichenbach , Craula, Zimmern, Alterstedt, Weberstedt , Mülverstedt , Flarchheim , Kammerforst , Oppershausen , Langula , Niederdorla , Oberdorla , Mühlhausen. The geological surface of Hainich

2220-534: The Truth ;; tho' they are not all agreed ... Compound Substances are made up of two or more simple Substances ... So a Needle is simple Body, being made only of Steel; but a Sword or a Knife is a compound because its ... Handle is made of Materials different from the Blade. Any substance consisting of two or more different types of atoms ( chemical elements ) in a fixed stoichiometric proportion can be termed

2280-523: The constituent particles, and particle size . These physical properties are the result of the processes that formed the rocks. Over the course of time, rocks can be transformed from one type into another, as described by a geological model called the rock cycle . This transformation produces three general classes of rock: igneous , sedimentary and metamorphic . Those three classes are subdivided into many groups. There are, however, no hard-and-fast boundaries between allied rocks. By increase or decrease in

2340-411: The development of metallurgy . Chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities ) containing atoms from more than one chemical element held together by chemical bonds . A molecule consisting of atoms of only one element is therefore not a compound. A compound can be transformed into a different substance by

2400-496: The earliest humans. This early period, called the Stone Age , saw the development of many stone tools. Stone was then used as a major component in the construction of buildings and early infrastructure . Mining developed to extract rocks from the Earth and obtain the minerals within them, including metals . Modern technology has allowed the development of new human-made rocks and rock-like substances, such as concrete . Geology

2460-606: The earth's surface by the accumulation and cementation of fragments of earlier rocks, minerals, and organisms or as chemical precipitates and organic growths in water ( sedimentation ). This process causes clastic sediments (pieces of rock) or organic particles ( detritus ) to settle and accumulate or for minerals to chemically precipitate ( evaporite ) from a solution . The particulate matter then undergoes compaction and cementation at moderate temperatures and pressures ( diagenesis ). Before being deposited, sediments are formed by weathering of earlier rocks by erosion in

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2520-427: The earth, from an ore body, vein or seam . The term also includes the removal of soil. Materials recovered by mining include base metals , precious metals , iron , uranium , coal , diamonds , limestone , oil shale , rock salt , potash , construction aggregate and dimension stone . Mining is required to obtain any material that cannot be grown through agricultural processes, or created artificially in

2580-400: The fixed ratios. Many solid chemical substances—for example many silicate minerals —are chemical substances, but do not have simple formulae reflecting chemically bonding of elements to one another in fixed ratios; even so, these crystalline substances are often called " non-stoichiometric compounds ". It may be argued that they are related to, rather than being chemical compounds, insofar as

2640-462: The forestry service in Creuzburg . The forests belong to the municipality of Mühlhausen and to the cooperatives of Oberdorla, Niederdorla, Langula and Kammerforst. Selective tree cutting and uneven-aged management are dominant in the beech forests. Sycamore maple and Chequer tree are bringing the best yield. In former times oaks and hornbeam were favored. A traditional trail is Rennstieg . It

2700-513: The four Elements, of which all earthly Things were compounded; and they suppos'd the Heavens to be a Quintessence, or fifth sort of Body, distinct from all these : But, since experimental Philosophy ... have been better understood, this Doctrine has been abundantly refuted. The Chymists make Spirit, Salt, Sulphur, Water and Earth to be their five Elements, because they can reduce all terrestrial Things to these five : This seems to come nearer

2760-402: The ground; pressure is dominant, and temperature plays a smaller role. This is termed burial metamorphism, and it can result in rocks such as jade . Where both heat and pressure play a role, the mechanism is termed regional metamorphism. This is typically found in mountain-building regions. Depending on the structure, metamorphic rocks are divided into two general categories. Those that possess

2820-491: The kind of metals available from the rock of a region. Anthropic rock is synthetic or restructured rock formed by human activity. Concrete is recognized as a human-made rock constituted of natural and processed rock and having been developed since Ancient Rome . Rock can also be modified with other substances to develop new forms, such as epoxy granite . Artificial stone has also been developed, such as Coade stone . Geologist James R. Underwood has proposed anthropic rock as

2880-431: The land to prepare it for other uses once mining ceases. Mining processes may create negative impacts on the environment both during the mining operations and for years after mining has ceased. These potential impacts have led to most of the world's nations adopting regulations to manage negative effects of mining operations. Stone tools have been used for millions of years by humans and earlier hominids . The Stone Age

2940-418: The original rock was formed. This process is called metamorphism , meaning to "change in form". The result is a profound change in physical properties and chemistry of the stone. The original rock, known as the protolith , transforms into other mineral types or other forms of the same minerals, by recrystallization . The temperatures and pressures required for this process are always higher than those found at

3000-425: The particles of clastic sedimentary rocks can be further classified by grain size . The smallest sediments are clay , followed by silt , sand , and gravel . Some systems include cobbles and boulders as measurements. Metamorphic rocks are formed by subjecting any rock type—sedimentary rock, igneous rock or another older metamorphic rock—to different temperature and pressure conditions than those in which

3060-536: The periodic table tend to have similar electronegativities , which means they have a similar affinity for electrons. Since neither element has a stronger affinity to donate or gain electrons, it causes the elements to share electrons so both elements have a more stable octet . Ionic bonding occurs when valence electrons are completely transferred between elements. Opposite to covalent bonding, this chemical bond creates two oppositely charged ions. The metals in ionic bonding usually lose their valence electrons, becoming

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3120-466: The proportions of their minerals, they pass through gradations from one to the other; the distinctive structures of one kind of rock may thus be traced, gradually merging into those of another. Hence the definitions adopted in rock names simply correspond to selected points in a continuously graduated series. Igneous rock (derived from the Latin word igneus, meaning of fire, from ignis meaning fire)

3180-641: The rocks of other celestial objects. Rocks are usually grouped into three main groups: igneous rocks , sedimentary rocks and metamorphic rocks . Igneous rocks are formed when magma cools in the Earth's crust, or lava cools on the ground surface or the seabed. Sedimentary rocks are formed by diagenesis and lithification of sediments , which in turn are formed by the weathering , transport, and deposition of existing rocks. Metamorphic rocks are formed when existing rocks are subjected to such high pressures and temperatures that they are transformed without significant melting. Humanity has made use of rocks since

3240-494: The two or more atom requirement, though they often consist of molecules composed of multiple atoms (such as in the diatomic molecule H 2 , or the polyatomic molecule S 8 , etc.). Many chemical compounds have a unique numerical identifier assigned by the Chemical Abstracts Service (CAS): its CAS number . There is varying and sometimes inconsistent nomenclature differentiating substances, which include truly non-stoichiometric examples, from chemical compounds, which require

3300-455: The types of bonds in compounds differ based on the types of elements present in the compound. London dispersion forces are the weakest force of all intermolecular forces . They are temporary attractive forces that form when the electrons in two adjacent atoms are positioned so that they create a temporary dipole . Additionally, London dispersion forces are responsible for condensing non polar substances to liquids, and to further freeze to

3360-621: The universe's celestial bodies. In the Solar System , Mars , Venus , and Mercury are composed of rock, as are many natural satellites , asteroids , and meteoroids . Meteorites that fall to Earth provide evidence of extraterrestrial rocks and their composition. They are typically heavier than rocks on Earth. Asteroid rocks can also be brought to Earth through space missions, such as the Hayabusa mission. Lunar rocks and Martian rocks have also been studied. The use of rock has had

3420-421: The variability in their compositions is often due to either the presence of foreign elements trapped within the crystal structure of an otherwise known true chemical compound , or due to perturbations in structure relative to the known compound that arise because of an excess of deficit of the constituent elements at places in its structure; such non-stoichiometric substances form most of the crust and mantle of

3480-408: Was a period of widespread stone tool usage. Early Stone Age tools were simple implements, such as hammerstones and sharp flakes. Middle Stone Age tools featured sharpened points to be used as projectile points , awls, or scrapers . Late Stone Age tools were developed with craftsmanship and distinct cultural identities. Stone tools were largely superseded by copper and bronze tools following

3540-456: Was formed. Most rocks contain silicate minerals , compounds that include silica tetrahedra in their crystal lattice , and account for about one-third of all known mineral species and about 95% of the earth's crust . The proportion of silica in rocks and minerals is a major factor in determining their names and properties. Rocks are classified according to characteristics such as mineral and chemical composition, permeability , texture of

3600-789: Was quarried for construction as early as 4000 BCE in Egypt, and stone was used to build fortifications in Inner Mongolia as early as 2800 BCE. The soft rock, tuff , is common in Italy, and the Romans used it for many buildings and bridges. Limestone was widely used in construction in the Middle Ages in Europe and remained popular into the 20th century. Mining is the extraction of valuable minerals or other geological materials from

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