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124-454: The organisation supports the professional development of its members who are involved in the fields of chemistry , life sciences and process technology . The organisation is actively involved in protecting the interests of its members. Furthermore, its supports the development and spread of knowledge and inspiration in the field of chemistry. It publishes journals, books and databases, as well as hosting conferences, seminars and workshops. In

248-440: A chemical equation . While in a non-nuclear chemical reaction the number and kind of atoms on both sides of the equation are equal, for a nuclear reaction this holds true only for the nuclear particles viz. protons and neutrons. The sequence of steps in which the reorganization of chemical bonds may be taking place in the course of a chemical reaction is called its mechanism . A chemical reaction can be envisioned to take place in

372-463: A certain level of independence from the bishops and were not willing to cede this to their new lord. The heavily fortified castle Vredenburg was built to house a large garrison whose main task was to maintain control over the city. The castle would last less than 50 years before it was demolished in an uprising in the early stages of the Dutch Revolt . In 1579 the northern seven provinces signed

496-467: A chemical reaction is said to have occurred. A chemical reaction is therefore a concept related to the "reaction" of a substance when it comes in close contact with another, whether as a mixture or a solution ; exposure to some form of energy, or both. It results in some energy exchange between the constituents of the reaction as well as with the system environment, which may be designed vessels—often laboratory glassware . Chemical reactions can result in

620-470: A chemical transformation is the rearrangement of electrons in the chemical bonds between atoms. It can be symbolically depicted through a chemical equation , which usually involves atoms as subjects. The number of atoms on the left and the right in the equation for a chemical transformation is equal. (When the number of atoms on either side is unequal, the transformation is referred to as a nuclear reaction or radioactive decay .) The type of chemical reactions

744-402: A definite composition and set of properties . A collection of substances is called a mixture. Examples of mixtures are air and alloys . The mole is a unit of measurement that denotes an amount of substance (also called chemical amount). One mole is defined to contain exactly 6.022 140 76 × 10 particles (atoms, molecules, ions, or electrons), where the number of particles per mole

868-412: A dense core called the atomic nucleus surrounded by a space occupied by an electron cloud . The nucleus is made up of positively charged protons and uncharged neutrons (together called nucleons ), while the electron cloud consists of negatively charged electrons which orbit the nucleus. In a neutral atom, the negatively charged electrons balance out the positive charge of the protons. The nucleus

992-541: A directed beam in a vacuum in a mass spectrometer . Charged polyatomic collections residing in solids (for example, common sulfate or nitrate ions) are generally not considered "molecules" in chemistry. Some molecules contain one or more unpaired electrons, creating radicals . Most radicals are comparatively reactive, but some, such as nitric oxide (NO) can be stable. The "inert" or noble gas elements ( helium , neon , argon , krypton , xenon and radon ) are composed of lone atoms as their smallest discrete unit, but

1116-797: A fundamental level. For example, chemistry explains aspects of plant growth ( botany ), the formation of igneous rocks ( geology ), how atmospheric ozone is formed and how environmental pollutants are degraded ( ecology ), the properties of the soil on the Moon ( cosmochemistry ), how medications work ( pharmacology ), and how to collect DNA evidence at a crime scene ( forensics ). Chemistry has existed under various names since ancient times. It has evolved, and now chemistry encompasses various areas of specialisation, or subdisciplines, that continue to increase in number and interrelate to create further interdisciplinary fields of study. The applications of various fields of chemistry are used frequently for economic purposes in

1240-407: A highway ( Catherijnebaan ). Protest against further modernisation of the city centre followed even before the last buildings were finalised. In the early 21st century, the whole area is undergoing change again. The redeveloped music centre TivoliVredenburg opened in 2014 with the original Vredenburg and Tivoli concert and rock and jazz halls brought together in a single building. Utrecht experiences

1364-411: A number of steps, each of which may have a different speed. Many reaction intermediates with variable stability can thus be envisaged during the course of a reaction. Reaction mechanisms are proposed to explain the kinetics and the relative product mix of a reaction. Many physical chemists specialize in exploring and proposing the mechanisms of various chemical reactions. Several empirical rules, like

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1488-461: A positive hydrogen ion to another substance in a chemical reaction; by extension, a base is the substance which receives that hydrogen ion. Utrecht Utrecht ( / ˈ j uː t r ɛ k t / YOO -trekt , Dutch: [ˈytrɛxt] ; Utrecht dialect : Ut(e)reg [ˈyt(ə)ʁɛχ] ) is the fourth-largest city of the Netherlands , as well as the capital and

1612-405: A pure chemical substance that has its unique set of chemical properties, that is, its potential to undergo a certain set of chemical reactions with other substances. However, this definition only works well for substances that are composed of molecules, which is not true of many substances (see below). Molecules are typically a set of atoms bound together by covalent bonds , such that the structure

1736-609: A substance may undergo and the energy changes that may accompany it are constrained by certain basic rules, known as chemical laws . Energy and entropy considerations are invariably important in almost all chemical studies. Chemical substances are classified in terms of their structure , phase, as well as their chemical compositions . They can be analyzed using the tools of chemical analysis , e.g. spectroscopy and chromatography . Scientists engaged in chemical research are known as chemists . Most chemists specialize in one or more sub-disciplines. Several concepts are essential for

1860-417: A temperate oceanic climate ( Köppen : Cfb ) similar to all of the Netherlands . Utrecht city had a population of 361,924 in 2022. It is a growing municipality and projections are that the population will surpass 392,000 by 2025. As of November 2019, the city of Utrecht has a population of 357,179. Utrecht has a young population, with many inhabitants in the age category from 20 and 30 years, due to

1984-414: Is a pure substance which is composed of a single type of atom, characterized by its particular number of protons in the nuclei of its atoms, known as the atomic number and represented by the symbol Z . The mass number is the sum of the number of protons and neutrons in a nucleus. Although all the nuclei of all atoms belonging to one element will have the same atomic number, they may not necessarily have

2108-409: Is a set of states of a chemical system that have similar bulk structural properties, over a range of conditions, such as pressure or temperature . Physical properties, such as density and refractive index tend to fall within values characteristic of the phase. The phase of matter is defined by the phase transition , which is when energy put into or taken out of the system goes into rearranging

2232-606: Is a station on the night service , providing an all-night service to (among others) Schiphol Airport, Amsterdam and Rotterdam, seven days a week. International InterCityExpress (ICE) services to Germany through Arnhem call at Utrecht Centraal. Regular local trains to all areas surrounding Utrecht also depart from Utrecht Centraal; and service several smaller stations: Utrecht Lunetten ; Utrecht Vaartsche Rijn ; Utrecht Overvecht ; Utrecht Leidsche Rijn ; Utrecht Terwijde ; Utrecht Zuilen and Vleuten . A former station Utrecht Maliebaan closed in 1939 and has since been converted into

2356-582: Is a very useful means for predicting the feasibility of a reaction and determining the state of equilibrium of a chemical reaction, in chemical thermodynamics . A reaction is feasible only if the total change in the Gibbs free energy is negative, Δ G ≤ 0 {\displaystyle \Delta G\leq 0\,} ; if it is equal to zero the chemical reaction is said to be at equilibrium . There exist only limited possible states of energy for electrons, atoms and molecules. These are determined by

2480-546: Is also informally considered the "capital" of the Dutch games industry . It was named by Business Finland in 2023 as one of several capitals for the European games industry as a whole. Utrecht's influence in this field was caused by video game development courses at its universities, which were the first such courses in Europe when launched in 2002. Since 2008 Utrecht has also been home to

2604-422: Is also possible to define analogs in two-dimensional systems, which has received attention for its relevance to systems in biology . Atoms sticking together in molecules or crystals are said to be bonded with one another. A chemical bond may be visualized as the multipole balance between the positive charges in the nuclei and the negative charges oscillating about them. More than simple attraction and repulsion,

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2728-439: Is also used to identify the composition of remote objects – like stars and distant galaxies – by analyzing their radiation spectra. The term chemical energy is often used to indicate the potential of a chemical substance to undergo a transformation through a chemical reaction or to transform other chemical substances. When a chemical substance is transformed as a result of its interaction with another substance or with energy,

2852-526: Is composed of gaseous matter that has been completely ionized, usually through high temperature. A substance can often be classified as an acid or a base . There are several different theories which explain acid–base behavior. The simplest is Arrhenius theory , which states that an acid is a substance that produces hydronium ions when it is dissolved in water, and a base is one that produces hydroxide ions when dissolved in water. According to Brønsted–Lowry acid–base theory , acids are substances that donate

2976-591: Is currently operated by the private transport company Qbuzz . On 16 December 2019 the new tram line to the Uithof started operating, creating a direct mass transit connection from the central station to the main Utrecht university campus. The main local and regional bus station of Utrecht is located adjacent to Utrecht Centraal railway station, at the East and West entrances. Due to large-scale renovation and construction works at

3100-472: Is dense; the mass of a nucleon is approximately 1,836 times that of an electron, yet the radius of an atom is about 10,000 times that of its nucleus. The atom is also the smallest entity that can be envisaged to retain the chemical properties of the element, such as electronegativity , ionization potential , preferred oxidation state (s), coordination number , and preferred types of bonds to form (e.g., metallic , ionic , covalent ). A chemical element

3224-624: Is dominated by the Dom Tower , the tallest belfry in the Netherlands and originally part of the Cathedral of Saint Martin . An ongoing debate is over whether any building in or near the centre of town should surpass the Dom Tower in height (112 m [367 ft]). Nevertheless, some tall buildings are now being constructed that will become part of the skyline of Utrecht. The second-tallest building of

3348-652: Is done at the Utrecht School of the Arts . The Centraal Museum has many exhibitions on the arts, including a permanent exhibition on the works of Utrecht resident illustrator Dick Bruna , who is best known for creating Miffy ("Nijntje", in Dutch). BAK, [Dutch: "Basis voor Actuele Kunst," Basis for Contemporary Art] offers contemporary art exhibitions and public events, as well as a Fellowship program for practitioners involved in contemporary arts, theory and activisms. Although street art

3472-464: Is electrically neutral and all valence electrons are paired with other electrons either in bonds or in lone pairs . Thus, molecules exist as electrically neutral units, unlike ions. When this rule is broken, giving the "molecule" a charge, the result is sometimes named a molecular ion or a polyatomic ion. However, the discrete and separate nature of the molecular concept usually requires that molecular ions be present only in well-separated form, such as

3596-516: Is home of one of the locations of TIAS School for Business and Society , focused on post-experience management education and the largest management school of its kind in the Netherlands. In 2008, its executive MBA program was rated the 24th best program in the world by the Financial Times . Utrecht is also home to two other large institutions of higher education: the vocational university Hogeschool Utrecht (37,000 students), with locations in

3720-551: Is known as the Avogadro constant . Molar concentration is the amount of a particular substance per volume of solution , and is commonly reported in mol/ dm . In addition to the specific chemical properties that distinguish different chemical classifications, chemicals can exist in several phases. For the most part, the chemical classifications are independent of these bulk phase classifications; however, some more exotic phases are incompatible with certain chemical properties. A phase

3844-539: Is more easily transferred between substances relative to light or other forms of electronic energy. For example, ultraviolet electromagnetic radiation is not transferred with as much efficacy from one substance to another as thermal or electrical energy. The existence of characteristic energy levels for different chemical substances is useful for their identification by the analysis of spectral lines . Different kinds of spectra are often used in chemical spectroscopy , e.g. IR , microwave , NMR , ESR , etc. Spectroscopy

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3968-455: Is sometimes argued that the close by municipalities De Bilt , Zeist , Houten , Vianen , Driebergen-Rijsenburg ( Utrechtse Heuvelrug ), and Bunnik should also be counted towards the Utrecht agglomeration, bringing the total to 640,000 inhabitants. The larger region, including slightly more remote cities such as Woerden and Amersfoort , counts up to 820,000 inhabitants. Utrecht's cityscape

4092-496: Is still in the city centre at Neude square, but is now serving as library, see also Utrecht Post Office . Another landmark is the old centre and the canal structure in the inner city. The Oudegracht is a curved canal, partly following the ancient main branch of the Rhine . It is lined with the unique wharf-basement structures that create a two-level street along the canals. The inner city has largely retained its medieval structure, and

4216-429: Is subdivided into 10 city quarters, all of which have their own neighbourhood council and service centre for civil affairs. Utrecht is the centre of a densely populated area, a fact which makes concise definitions of its agglomeration difficult, and somewhat arbitrary. The smaller Utrecht agglomeration of continuously built-up areas counts some 420,000 inhabitants and includes Nieuwegein , IJsselstein and Maarssen . It

4340-468: Is the crystal structure , or arrangement, of the atoms. Another phase commonly encountered in the study of chemistry is the aqueous phase, which is the state of substances dissolved in aqueous solution (that is, in water). Less familiar phases include plasmas , Bose–Einstein condensates and fermionic condensates and the paramagnetic and ferromagnetic phases of magnetic materials. While most familiar phases deal with three-dimensional systems, it

4464-458: Is the quantum mechanical model . Traditional chemistry starts with the study of elementary particles , atoms , molecules , substances , metals , crystals and other aggregates of matter . Matter can be studied in solid, liquid, gas and plasma states , in isolation or in combination. The interactions, reactions and transformations that are studied in chemistry are usually the result of interactions between atoms, leading to rearrangements of

4588-502: Is the probability of a molecule to have energy greater than or equal to E at the given temperature T. This exponential dependence of a reaction rate on temperature is known as the Arrhenius equation . The activation energy necessary for a chemical reaction to occur can be in the form of heat, light, electricity or mechanical force in the form of ultrasound . A related concept free energy , which also incorporates entropy considerations,

4712-517: Is useful in identifying periodic trends . A compound is a pure chemical substance composed of more than one element. The properties of a compound bear little similarity to those of its elements. The standard nomenclature of compounds is set by the International Union of Pure and Applied Chemistry (IUPAC). Organic compounds are named according to the organic nomenclature system. The names for inorganic compounds are created according to

4836-578: The American Chemical Society in 1876. Denmark followed in 1879, Sweden in 1883, Finland in 1891 and Norway in 1893, while the Société Chimique de Belge was established in Brussels in 1887. In order to successfully establish a Dutch chemical association, it was first of all necessary to find out whether a sufficient number of members could be counted on. Following the medical yearbook for

4960-572: The Dutch Railway Museum . Utrecht is the location of the headquarters of Nederlandse Spoorwegen (English: Dutch Railways ), the largest rail operator in the Netherlands, and ProRail , the state-owned company responsible for the construction and maintenance of the country's rail infrastructure. The Utrecht sneltram is a light rail scheme running southwards from Utrecht Centraal to the suburbs of IJsselstein , Kanaleneiland , Lombok and Nieuwegein . The sneltram began operations in 1983 and

5084-694: The Euro-VI standard as well as electric buses for inner-city transport. Regional buses from the city are operated by Arriva and Connexxion . The Utrecht Centraal railway station is also served by the pan-European services of Eurolines . Furthermore, it acts as departure and arrival place of many coach companies serving holiday resorts in Spain and France—and during winter in Austria and Switzerland . Like most Dutch cities, Utrecht has an extensive network of cycle paths , making cycling safe and popular. 33% of journeys within

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5208-618: The Frisians . Pope Sergius I appointed their leader, Saint Willibrordus , as bishop of the Frisians. The tenure of Willibrordus is generally considered to be the beginning of the Bishopric of Utrecht . In 723, the Frankish leader Charles Martel bestowed the fortress in Utrecht and the surrounding lands as the base of the bishops. From then on Utrecht became one of the most influential seats of power for

5332-643: The High Middle Ages . It has been the religious centre of the Netherlands since the 8th century. In 1579, the Union of Utrecht was signed in the city to lay the foundations for the Dutch Republic . Utrecht was the most important city in the Netherlands until the Dutch Golden Age , when it was surpassed by Amsterdam as the country's cultural centre and most populous city. Utrecht is home to Utrecht University ,

5456-575: The Municipal Health Service in Amsterdam and chief of the associated chemical laboratory. The second volume appeared in 1901; the third in 1902. The editorial board was expanded with Dr. Albert Jacques Joseph van de Velde (1871-1956), director of the city laboratory in Ghent. The title therefore became: Scheikundig Jaarboekje voor Nederland, België en Nederlands Indië ( English : Chemical Yearbook for

5580-412: The Netherlands with 30,449 students (as of 2012 ). The university is partially based in the inner city as well as in the Uithof campus area, on the east side of the city. According to Shanghai Jiaotong University 's university ranking in 2014, it is the 57th-best university in the world. Utrecht also houses the much smaller University of Humanistic Studies , which houses about 400 students. Utrecht

5704-529: The Nieuwe Hollandse Waterlinie were moved east of Utrecht. The town walls could now be demolished to allow for expansion. The moats remained intact and formed an important feature of the Zocher plantsoen, an English style landscape park that remains largely intact today. Growth of the city increased when, in 1843, a railway connecting Utrecht to Amsterdam was opened. After that, Utrecht gradually became

5828-565: The Roman emperor Claudius decided the empire should not expand further north. To consolidate the border, the Limes Germanicus defense line was constructed along the main branch of the river Rhine , which at that time traversed a more northern route (now known as the Kromme Rijn ) compared to today's Rhine flow. These fortresses were designed to house a cohort of about 500 Roman soldiers. Near

5952-594: The Teutonic Knights . Besides these buildings which belonged to the bishopric, an additional four parish churches were constructed in the city: the Jacobikerk ( dedicated to Saint James ), founded in the 11th century, with the current Gothic church dating back to the 14th century; the Buurkerk (Neighbourhood-church) of the 11th-century parish in the centre of the city; Nicolaichurch (dedicated to Saint Nicholas ), from

6076-400: The Union of Utrecht treaty (Dutch: Unie van Utrecht), in which they decided to join forces against Spanish rule. The Union of Utrecht is seen as the beginning of the Dutch Republic . In 1580, the new and predominantly Protestant state abolished the bishoprics, including the archbishopric of Utrecht. The stadtholders disapproved of the independent course of the Utrecht bourgeoisie and brought

6200-771: The University of Amsterdam on 21 oktober 1896 with Hendrik Willem Bakhuis Roozeboom as supervisor. Rutten and Jorissen became friends and discussed the possibilities of organizing the Dutch chemists. There were already chemical associations in neighboring countries for a long time: the Chemical Society in London was founded in 1841, the Société chimique de France in 1857, the Deutsche Chemische Gesellschaft zu Berlin in 1867 and

6324-505: The Woodward–Hoffmann rules often come in handy while proposing a mechanism for a chemical reaction. According to the IUPAC gold book, a chemical reaction is "a process that results in the interconversion of chemical species." Accordingly, a chemical reaction may be an elementary reaction or a stepwise reaction . An additional caveat is made, in that this definition includes cases where

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6448-455: The chemical bonds which hold atoms together. Such behaviors are studied in a chemistry laboratory . The chemistry laboratory stereotypically uses various forms of laboratory glassware . However glassware is not central to chemistry, and a great deal of experimental (as well as applied/industrial) chemistry is done without it. A chemical reaction is a transformation of some substances into one or more different substances. The basis of such

6572-487: The chemical industry . The word chemistry comes from a modification during the Renaissance of the word alchemy , which referred to an earlier set of practices that encompassed elements of chemistry, metallurgy , philosophy , astrology , astronomy , mysticism , and medicine . Alchemy is often associated with the quest to turn lead or other base metals into gold, though alchemists were also interested in many of

6696-433: The duet rule , and in this way they are reaching the electron configuration of the noble gas helium , which has two electrons in its outer shell. Similarly, theories from classical physics can be used to predict many ionic structures. With more complicated compounds, such as metal complexes , valence bond theory is less applicable and alternative approaches, such as the molecular orbital theory, are generally used. In

6820-499: The inorganic nomenclature system. When a compound has more than one component, then they are divided into two classes, the electropositive and the electronegative components. In addition the Chemical Abstracts Service has devised a method to index chemical substances. In this scheme each chemical substance is identifiable by a number known as its CAS registry number . A molecule is the smallest indivisible portion of

6944-500: The interconversion of conformers is experimentally observable. Such detectable chemical reactions normally involve sets of molecular entities as indicated by this definition, but it is often conceptually convenient to use the term also for changes involving single molecular entities (i.e. 'microscopic chemical events'). An ion is a charged species, an atom or a molecule, that has lost or gained one or more electrons. When an atom loses an electron and thus has more protons than electrons,

7068-529: The intermolecular forces of a substance are such that the energy of the surroundings is not sufficient to overcome them, it occurs in a more ordered phase like liquid or solid as is the case with water (H 2 O); a liquid at room temperature because its molecules are bound by hydrogen bonds . Whereas hydrogen sulfide (H 2 S) is a gas at room temperature and standard pressure, as its molecules are bound by weaker dipole–dipole interactions . The transfer of energy from one chemical substance to another depends on

7192-438: The size of energy quanta emitted from one substance. However, heat energy is often transferred more easily from almost any substance to another because the phonons responsible for vibrational and rotational energy levels in a substance have much less energy than photons invoked for the electronic energy transfer. Thus, because vibrational and rotational energy levels are more closely spaced than electronic energy levels, heat

7316-515: The 12th century, and the 13th-century Geertekerk (dedicated to Saint Gertrude of Nivelles ). Its location on the banks of the river Rhine allowed Utrecht to become an important trade centre in the Northern Netherlands. The growing town was granted city rights by Henry V at Utrecht on 2 June 1122. When the main flow of the Rhine moved south, the old bed which still flowed through the heart of

7440-468: The 16th century), on the Dom square, dating back to the early 8th century. Saint John (Janskerk), originating in 1040; Saint Peter , building started in 1039 and Saint Mary 's church building started around 1090 (demolished in the early 19th century, cloister survives). Besides these churches, the city housed St. Paul's Abbey , the 15th-century beguinage of St. Nicholas , and a 14th-century chapter house of

7564-527: The Catholic Church in the Netherlands. The archbishops of Utrecht were based at the uneasy northern border of the Carolingian Empire . In addition, the city of Utrecht had competition from the nearby trading centre Dorestad . After the fall of Dorestad around 850, Utrecht became one of the most important cities in the Netherlands. The importance of Utrecht as a centre of Christianity is illustrated by

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7688-582: The East, and Lombok to the West were developed. New middle-class residential areas, such as Tuindorp and Oog in Al , were built in the 1920s and 1930s. During this period, several Jugendstil houses and office buildings were built, followed by Rietveld who built the Rietveld Schröder House (1924), and Dudok 's construction of the city theatre (1941). During World War II , Utrecht was held by German forces until

7812-611: The French invasion in 1672 (the Disaster Year , Dutch: Rampjaar). The French invasion was stopped just west of Utrecht at the Old Hollandic Waterline . In 1674, only two years after the French left, the centre of Utrecht was struck by a tornado . The halt to building before construction of flying buttresses in the 15th century now proved to be the undoing of the cathedral of St Martin church's central section which collapsed, creating

7936-504: The Netherlands published since 1882, the two friends published a chemical yearbook in 1898 that contained an address list of Dutch chemists at home and abroad. The editors consisted of Jorissen, Rutten, the Amsterdam pharmacist and chemist Bernardus Adrianus van Ketel (1862-1928), H.C. Prinsen Geerligs (born 1864), director of the sugar cane testing station in Kagok, Tegal ( Java ), and Dr. Lodewijk Theodorus Reicher (1857-1943), chemical mechanic at

8060-635: The Netherlands, Belgium and the Dutch East Indies). In the meantime, the Journal of Applied Chemistry and Hygiene was founded in 1897 of which Jorissen became co-editor. The chemical yearbook and the journal would play a major role in the founding of the Dutch Chemical Association. The society was founded on 15 April 1903 as the "Algemene Nederlandsche Chemische Vereeniging" ( English : General Netherlands Chemical Society), and renamed on 4 July of

8184-443: The Netherlands, i.e. that of 's-Hertogenbosch , Utrecht , Zwolle , Groningen , Haarlem , and Rotterdam . Chemistry Chemistry is the scientific study of the properties and behavior of matter . It is a physical science within the natural sciences that studies the chemical elements that make up matter and compounds made of atoms , molecules and ions : their composition, structure, properties, behavior and

8308-500: The Valence Shell Electron Pair Repulsion model ( VSEPR ), and the concept of oxidation number can be used to explain molecular structure and composition. An ionic bond is formed when a metal loses one or more of its electrons, becoming a positively charged cation, and the electrons are then gained by the non-metal atom, becoming a negatively charged anion. The two oppositely charged ions attract one another, and

8432-491: The atom is a positively charged ion or cation . When an atom gains an electron and thus has more electrons than protons, the atom is a negatively charged ion or anion . Cations and anions can form a crystalline lattice of neutral salts , such as the Na and Cl ions forming sodium chloride , or NaCl. Examples of polyatomic ions that do not split up during acid–base reactions are hydroxide (OH ) and phosphate (PO 4 ). Plasma

8556-497: The bishop lost secular power over both Neder- and Oversticht—which included the city of Utrecht—to Charles V, Holy Roman Emperor . Charles V combined the Seventeen Provinces (the current Benelux and the northern parts of France) as a personal union. This ended the prince-bishopric of Utrecht, as the secular rule was now the lordship of Utrecht , with the religious power remaining with the bishop, although Charles V had gained

8680-560: The bishop, who controlled many lands outside of the city, and the citizens of Utrecht was not always easy. The bishop, for example dammed the Kromme Rijn at Wijk bij Duurstede to protect his estates from flooding. This threatened shipping for the city and led the city of Utrecht to commission a canal to ensure access to the town for shipping trade: the Vaartse Rijn, connecting Utrecht to the Hollandse IJssel at IJsselstein . In 1528

8804-457: The central nave , from 1420. By that time, however, the age of the great cathedrals had come to an end and declining finances prevented the ambitious project from being finished, the construction of the central nave being suspended before the planned flying buttresses could be finished. Besides the cathedral there were four collegiate churches in Utrecht: St. Salvator's Church (demolished in

8928-411: The changes they undergo during reactions with other substances . Chemistry also addresses the nature of chemical bonds in chemical compounds . In the scope of its subject, chemistry occupies an intermediate position between physics and biology . It is sometimes called the central science because it provides a foundation for understanding both basic and applied scientific disciplines at

9052-531: The chemistry, life sciences or process technology, and endorses the core values for chemists. The board decides on the admission of the members. The society does have the following categories of membership: The society is organised around 17 sections and associations that are based on subject areas, work groups, and local circles across the Netherlands. The sections and associations cover broad areas of chemistry but also contain many special interest groups for more specific areas: There are six local circles covering

9176-565: The city and the Uithof campus; and the HKU Utrecht School of the Arts (3,000 students). There are many schools for primary and secondary education, allowing parents to select from different philosophies and religions in the school as is inherent in the Dutch school system . Utrecht city has an active cultural life, and in the Netherlands is second only to Amsterdam. There are several theatres and theatre companies. The 1941 main city theatre

9300-407: The city are by bicycle, more than any other mode of transport. (Cars, for example, account for 30% of trips). Bicycles are used by young and old people, and by individuals and families. They are mostly traditional, upright, steel-framed bicycles, with few gears. There are also bucket bikes for carrying cargo such as groceries or small children. Thanks in part to the access provided by bicycles, 100% of

9424-483: The city in the early 19th century, required open lines of fire, thus prohibiting all permanent constructions until the middle of the 20th century on the east side of the city. Due to the past importance of Utrecht as a religious centre, several monumental churches were erected, many of which have survived. Most prominent is the Dom Church . Other notable churches include the romanesque St Peter's and St John's churches;

9548-399: The city of Utrecht. The most dominant of these was the Cathedral of Saint Martin , inside the old Roman fortress. The construction of the present Gothic building was begun in 1254 after an earlier romanesque construction had been badly damaged by fire. The choir and transept were finished from 1320 and were followed then by the ambitious Dom tower . The last part to be constructed was

9672-458: The city under much more direct control of the republic, shifting the power towards its dominant province Holland . This was the start of a long period of stagnation of trade and development in Utrecht. Utrecht remained an atypical city in the new republic being about 40% Catholic in the mid-17th century, and even more so among the elite groups, who included many rural nobility and gentry with town houses there. The fortified city temporarily fell to

9796-621: The city, the Rabobank -tower, was completed in 2010 and stands 105 m (344 ft) tall. Two antennas will increase that height to 120 m (394 ft). Two other buildings were constructed around the Nieuw Galgenwaard stadium (2007). These buildings, the 'Kantoortoren Galghenwert' and 'Apollo Residence', stand 85.5 m (280.5 ft) and 64.5 m (211.6 ft) high, respectively. The former Utrecht Main Post Office, built in 1924,

9920-412: The context of chemistry, energy is an attribute of a substance as a consequence of its atomic , molecular or aggregate structure . Since a chemical transformation is accompanied by a change in one or more of these kinds of structures, it is invariably accompanied by an increase or decrease of energy of the substances involved. Some energy is transferred between the surroundings and the reactants of

10044-565: The current Dom square between the tower and choir. In 1713, Utrecht hosted one of the first international peace negotiations when the Treaty of Utrecht settled the War of the Spanish Succession . Beginning in 1723, Utrecht became the centre of the non-Roman Old Catholic Churches in the world. In the early 19th century, the role of Utrecht as a fortified town had become obsolete. The fortifications of

10168-541: The election of the Utrecht-born Adriaan Florenszoon Boeyens as pope in 1522 (the last non-Italian pope before John Paul II ). When the Frankish rulers established the system of feudalism , the Bishops of Utrecht came to exercise worldly power as prince-bishops . The territory of the bishopric not only included the modern province of Utrecht (Nedersticht, 'lower Sticht '), but also extended to

10292-429: The energies and distributions characterize the availability of an electron to bond to another atom. The chemical bond can be a covalent bond , an ionic bond , a hydrogen bond or just because of Van der Waals force . Each of these kinds of bonds is ascribed to some potential. These potentials create the interactions which hold atoms together in molecules or crystals . In many simple compounds, valence bond theory ,

10416-577: The final section (after some delay) being opened on 19 August 2019. Utrecht is well-connected to the Dutch road network. Two of the most important major roads serve the city of Utrecht: the A12 and A2 motorways connect Amsterdam , Arnhem , The Hague and Maastricht , as well as Belgium and Germany. Other major motorways in the area are the Almere – Breda A27 and the Utrecht– Groningen A28 . Due to

10540-444: The formation or dissociation of molecules, that is, molecules breaking apart to form two or more molecules or rearrangement of atoms within or across molecules. Chemical reactions usually involve the making or breaking of chemical bonds. Oxidation, reduction , dissociation , acid–base neutralization and molecular rearrangement are some examples of common chemical reactions. A chemical reaction can be symbolically depicted through

10664-411: The fort, settlements grew that housed artisans , traders and soldiers' wives and children. In Roman times, the name of the Utrecht fortress was simply Traiectum , denoting its location at a possible Rhine crossing. Traiectum became Dutch Trecht; with the U from Old Dutch "uut" (downriver) added to distinguish U-trecht from Maas-tricht , on the river Meuse . In 11th-century official documents, it

10788-457: The general German surrender of the Netherlands on 5 May 1945. British and Canadian troops that had surrounded the city entered it after that surrender, on 7 May 1945. Following the end of World War II, the city grew considerably when new neighbourhoods such as Overvecht , Kanaleneiland , Hoograven  [ nl ] and Lunetten were built. Around 2000, the Leidsche Rijn housing area

10912-511: The gothic churches of St James and St Nicholas; and the Buurkerk, now converted into a museum for automatically playing musical instruments . Because of its central location, Utrecht is well connected to the rest of the Netherlands and has a well-developed public transport network. Utrecht Centraal is the main railway station of Utrecht and is the largest in the country. There are regular intercity services to all major Dutch cities, including direct services to Schiphol Airport . Utrecht Centraal

11036-472: The increasing traffic and the ancient city plan, traffic congestion is a common phenomenon in and around Utrecht, causing elevated levels of air pollutants . This has led to a passionate debate in the city about the best way to improve the city's air quality. Utrecht has an industrial port located on the Amsterdam-Rijnkanaal . The container terminal has a capacity of 80,000 containers a year. In 2003,

11160-447: The ionic bond is the electrostatic force of attraction between them. For example, sodium (Na), a metal, loses one electron to become an Na cation while chlorine (Cl), a non-metal, gains this electron to become Cl . The ions are held together due to electrostatic attraction, and that compound sodium chloride (NaCl), or common table salt, is formed. In a covalent bond, one or more pairs of valence electrons are shared by two atoms:

11284-566: The larger station area redevelopment plan and in 2014 gained additional halls that allowed its merger with the rock club Tivoli and the SJU jazzpodium. There are several other venues for music throughout the city. Young musicians are educated in the conservatory , a department of the Utrecht School of the Arts . There is a specialised museum of automatically playing musical instruments. There are many art galleries in Utrecht. There are also several foundations to support art and artists. Training of artists

11408-420: The largest university in the Netherlands, as well as several other institutions of higher education. Due to its central position within the country, it is an important hub for both rail and road transport ; it has the busiest railway station in the Netherlands, Utrecht Centraal . It has the second-highest number of cultural events in the Netherlands, after Amsterdam. In 2012, Lonely Planet included Utrecht in

11532-401: The main characteristics of a molecule is its geometry often called its structure . While the structure of diatomic , triatomic or tetra-atomic molecules may be trivial, ( linear , angular pyramidal etc.) the structure of polyatomic molecules, that are constituted of more than six atoms (of several elements) can be crucial for its chemical nature. A chemical substance is a kind of matter with

11656-506: The main hub of the Dutch railway network . With the Industrial Revolution finally gathering speed in the Netherlands and the ramparts taken down, Utrecht began to grow far beyond its medieval centre. When the Dutch government allowed the bishopric of Utrecht to be reinstated by Rome in 1853, Utrecht became the centre of Dutch Catholicism once more. From the 1880s onward, neighbourhoods such as Oudwijk, Wittevrouwen , Vogelenbuurt to

11780-579: The moat ringing the old town is largely intact. In the 1970s part of the moat was converted into a motorway. It was then converted back into a waterway, the work being finished in 2020. Because of the role of Utrecht as a fortified city, construction outside the medieval centre and its city walls was restricted until the 19th century. Surrounding the medieval core there is a ring of late-19th- and early-20th-century neighbourhoods, with newer neighbourhoods positioned farther out. The eastern part of Utrecht remains fairly open. The Dutch Water Line , moved east of

11904-457: The most populous city of the province of Utrecht . The municipality of Utrecht is located in the eastern part of the Randstad conurbation , in the very centre of mainland Netherlands, and includes Haarzuilens , Vleuten and De Meern . It has a population of 361,699 as of December 2021 . Utrecht's ancient city centre features many buildings and structures, several dating as far back as

12028-716: The most senior Dutch Roman Catholic leader. His ecclesiastical province covers the whole kingdom. Utrecht is also the see of the archbishop of the Old Catholic Church , titular head of the Union of Utrecht , and the location of the offices of the Protestant Church in the Netherlands , the main Dutch Protestant church. As of 2013, the largest religion is Christianity with 28% of the population being Christian, followed by Islam with 9.9% in 2016 and Hinduism with 0.8%. Religions in Utrecht (2013) The city of Utrecht

12152-602: The northeast. The feudal conflict of the Middle Ages heavily affected Utrecht. The prince-bishopric was involved in almost continuous conflicts with the Counts of Holland and the Dukes of Guelders . The Veluwe region was seized by Guelders, but large areas in the modern province of Overijssel remained as the Oversticht. Several churches and monasteries were built inside, or close to,

12276-419: The other isolated chemical elements consist of either molecules or networks of atoms bonded to each other in some way. Identifiable molecules compose familiar substances such as water, air, and many organic compounds like alcohol, sugar, gasoline, and the various pharmaceuticals . However, not all substances or chemical compounds consist of discrete molecules, and indeed most of the solid substances that make up

12400-490: The population consists of people with a recent migration background from Western countries, while 24.8% of the population has at least one parent who is of 'non-Western origin' (8.8% from Morocco, 4% Turkey, 3% Surinam and Dutch Caribbean and 9.1% of other countries). Utrecht has been the religious centre of the Netherlands since the 8th century. Currently it is the see of the Metropolitan Archbishop of Utrecht ,

12524-544: The population lives in a 15-minute city and more than 90% can get to the major destination types within 10 minutes. In 2014, the city council decided to build the world's largest bicycle parking station , near the Central Railway Station . This three-floor construction cost over €30 million and can hold 12,500 bicycles. The bicycle parking station was built in stages, with the first part opening in August 2017, and

12648-454: The port facilitated the transport of four million tons of cargo; mostly sand, gravel, fertiliser and fodder. Additionally, some tourist boat trips are organised from various places on the Oudegracht; and the city is connected to touristic shipping routes through sluices. Production industry constitutes a small part of the economy of Utrecht. The economy of Utrecht depends for a large part on

12772-415: The presence of a large university. About 52% of the population is female, 48% is male. The majority of households (52.5%) in Utrecht are single-person households. About 29% of people living in Utrecht are either married, or have another legal partnership. About 3% of the population of Utrecht is divorced. For 62.8% of the population of Utrecht both parents were born in the Netherlands. Approximately 12.4% of

12896-615: The questions of modern chemistry. The modern word alchemy in turn is derived from the Arabic word al-kīmīā ( الكیمیاء ). This may have Egyptian origins since al-kīmīā is derived from the Ancient Greek χημία , which is in turn derived from the word Kemet , which is the ancient name of Egypt in the Egyptian language. Alternately, al-kīmīā may derive from χημεία 'cast together'. The current model of atomic structure

13020-408: The railway station, the station's bus stops are changing frequently. As a general rule, westbound buses depart from the bus station on the west entrance, other buses from the east side station. Local buses in Utrecht are operated by Qbuzz ; its services include a high-frequency service to the Uithof university district. The local bus fleet is one of Europe's cleanest, using only buses compliant with

13144-473: The reaction absorbs heat from the surroundings. Chemical reactions are invariably not possible unless the reactants surmount an energy barrier known as the activation energy . The speed of a chemical reaction (at given temperature T) is related to the activation energy E, by the Boltzmann's population factor e − E / k T {\displaystyle e^{-E/kT}} – that

13268-433: The reaction in the form of heat or light ; thus the products of a reaction may have more or less energy than the reactants. A reaction is said to be exergonic if the final state is lower on the energy scale than the initial state; in the case of endergonic reactions the situation is the reverse. A reaction is said to be exothermic if the reaction releases heat to the surroundings; in the case of endothermic reactions ,

13392-544: The resulting electrically neutral group of bonded atoms is termed a molecule . Atoms will share valence electrons in such a way as to create a noble gas electron configuration (eight electrons in their outermost shell) for each atom. Atoms that tend to combine in such a way that they each have eight electrons in their valence shell are said to follow the octet rule . However, some elements like hydrogen and lithium need only two electrons in their outermost shell to attain this stable configuration; these atoms are said to follow

13516-524: The right to appoint new bishops. In 1559 the bishopric of Utrecht was raised to archbishopric to make it the religious centre of the Northern ecclesiastical province in the Seventeen Provinces. The transition from independence to a relatively minor part of a larger union was not easily accepted. To quell uprisings, Charles V struggled to exert his power over the city's citizens who had struggled to gain

13640-403: The rules of quantum mechanics , which require quantization of energy of a bound system. The atoms/molecules in a higher energy state are said to be excited. The molecules/atoms of substance in an excited energy state are often much more reactive; that is, more amenable to chemical reactions. The phase of a substance is invariably determined by its energy and the energy of its surroundings. When

13764-474: The same mass number; atoms of an element which have different mass numbers are known as isotopes . For example, all atoms with 6 protons in their nuclei are atoms of the chemical element carbon , but atoms of carbon may have mass numbers of 12 or 13. The standard presentation of the chemical elements is in the periodic table , which orders elements by atomic number. The periodic table is arranged in groups , or columns, and periods , or rows. The periodic table

13888-417: The same year as "Nederlandsche Chemische Vereeniging" (English: Netherlands Chemical Society). At the jubilee of 1953, the organisation was granted a Royal Charter (with the designation " Koninklijke ") by Queen Juliana of the Netherlands and thereby became the "Koninklijke Nederlandse Chemische Vereniging" ( English : Royal Netherlands Chemical Society). Membership is open to anyone who works or studies in

14012-482: The several large institutions located in the city. It is the centre of the Dutch railway network and the location of the head office of Nederlandse Spoorwegen . ProRail is headquartered in De Inktpot  [ nl ] (The Inkwell), the largest brick building in the Netherlands (the "UFO" featured on its façade stems from an art program in 2000). Rabobank , a large bank, has its headquarters in Utrecht. Utrecht

14136-641: The solid crust, mantle, and core of the Earth are chemical compounds without molecules. These other types of substances, such as ionic compounds and network solids , are organized in such a way as to lack the existence of identifiable molecules per se . Instead, these substances are discussed in terms of formula units or unit cells as the smallest repeating structure within the substance. Examples of such substances are mineral salts (such as table salt ), solids like carbon and diamond, metals, and familiar silica and silicate minerals such as quartz and granite. One of

14260-695: The structure of the system, instead of changing the bulk conditions. Sometimes the distinction between phases can be continuous instead of having a discrete boundary; in this case the matter is considered to be in a supercritical state. When three states meet based on the conditions, it is known as a triple point and since this is invariant, it is a convenient way to define a set of conditions. The most familiar examples of phases are solids , liquids , and gases . Many substances exhibit multiple solid phases. For example, there are three phases of solid iron (alpha, gamma, and delta) that vary based on temperature and pressure. A principal difference between solid phases

14384-412: The studio incubator program Dutch Game Garden , which has launched a number of studios in the area. By 2014 the program had created 200 jobs. Utrecht is also home to Nixxes Software (a PlayStation Studios subsidiary) as well as Sokpop Collective . Utrecht hosts several large institutions of higher education. The most prominent of these is Utrecht University (est. 1636), the largest university of

14508-421: The study of chemistry; some of them are: In chemistry, matter is defined as anything that has rest mass and volume (it takes up space) and is made up of particles . The particles that make up matter have rest mass as well – not all particles have rest mass, such as the photon . Matter can be a pure chemical substance or a mixture of substances. The atom is the basic unit of chemistry. It consists of

14632-531: The top 10 of the world's unsung places. Although there is some evidence of earlier inhabitation in the region of Utrecht, dating back to the Stone Age (app. 2200 BCE ) and settling in the Bronze Age (app. 1800–800 BCE), the founding date of the city is usually related to the construction of a Roman fortification ( castellum ), probably built in around 50 CE . A series of such fortresses were built after

14756-403: The town became ever more canalized ; and the wharf system was built as an inner city harbour system. On the wharfs, storage facilities ( werfkelders ) were built, on top of which the main street, including houses, was constructed. The wharfs and the cellars are accessible from a platform at water level with stairs descending from the street level to form a unique structure. The relations between

14880-601: The years of 1896 and 1897, two Dutch chemists Willem Paulinus Jorissen and Johannes Rutten made plans to found an Association of Dutch Chemists. Rutten (1873-1946) had obtained the degree of technologist at the Polytechnic School in Delft (now Delft University of Technology ) in 1896 and was appointed chemist at the former Central Guanofabrieken (now AkzoNobel ) at Kralingseveer in Rotterdam . Jorissen obtained his PhD degree at

15004-498: Was Latinized as Ultra Traiectum. Around the year 200, the wooden walls of the fortification were replaced by sturdier tuff stone walls, remnants of which are still to be found below the buildings around Dom Square. From the middle of the 3rd century, Germanic tribes regularly invaded the Roman territories. After around 275 the Romans could no longer maintain the northern border, and Utrecht

15128-523: Was abandoned. Little is known about the period from 270 to 650. Utrecht is first spoken of again several centuries after the Romans left. Under the influence of the growing realms of the Franks , during Dagobert I 's reign in the 7th century, a church was built within the walls of the Roman fortress. In ongoing border conflicts with the Frisians , this first church was destroyed. By the mid-7th century, British, English and Irish missionaries set out to convert

15252-569: Was built by Dudok . In addition to theatres, there is a large number of cinemas including three arthouse cinemas. Utrecht is host to the international Early Music Festival (Festival Oude Muziek, for music before 1800) and the Netherlands Film Festival . The city has an important classical music hall Vredenburg (1979 by Herman Hertzberger ). Its acoustics are considered among the best of the 20th-century original music halls. The original Vredenburg music hall has been redeveloped as part of

15376-429: Was developed as an extension of the city to the west. The area surrounding Utrecht Centraal railway station and the station itself were developed following modernist ideas of the 1960s, in a brutalist style. This development led to the construction of the shopping mall Hoog Catharijne  [ nl ] , the music centre Vredenburg ( Hertzberger , 1979), and conversion of part of the ancient canal structure into

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