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68-454: Abdul Wali Khan University consists of six faculties, which have the following departments: ● Agronomy ● Entomology ● Food Science and Technology ● Horticulture The university has several campuses, each with library facilities: There is also a digital library serving all campuses. The University College of Science in Shankar has departments of Chemistry and Computer Science . It

136-440: 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

204-467: 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

272-470: 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

340-412: 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

408-535: 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

476-552: A humanist, Agricola was intent on purifying words and returning them to their classical roots. He had no intent to make a semantic distinction between chymia and alchymia . During the later sixteenth century Agricola's new coinage slowly propagated. It seems to have been adopted in most of the vernacular European languages following Conrad Gessner 's adoption of it in his extremely popular pseudonymous work, Thesaurus Euonymi Philiatri De remediis secretis: Liber physicus, medicus, et partim etiam chymicus (Zurich 1552). Gessner's work

544-426: A journalism student at the university, was murdered by a mob apparently including university employees and some of his classmates on the false suspicion of uploading blasphemous content on the social networking site Facebook. (May 1, 2020–Present) Chemistry Chemistry is the scientific study of the properties and behavior of matter . It is a physical science within the natural sciences that studies

612-411: 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

680-424: 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

748-549: A positive hydrogen ion to another substance in a chemical reaction; by extension, a base is the substance which receives that hydrogen ion. Chemistry (word) The word chemistry derives from the word alchemy , which is found in various forms in European languages. The word 'alchemy' itself derives from the Arabic word al-kīmiyāʾ ( الكيمياء ), wherein al- is the definite article 'the'. The ultimate origin of

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816-405: 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

884-609: 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

952-414: 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

1020-409: 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

1088-586: 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

1156-422: 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,

1224-439: 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,

1292-464: 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 is known as the Avogadro constant . Molar concentration is the amount of

1360-523: 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 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

1428-472: Is defined as follows: Later medieval Latin had alchimia / alchymia "alchemy", alchimicus "alchemical", and alchimista "alchemist". The mineralogist and humanist Georg Agricola (died 1555) was the first to drop the Arabic definite article al- . In his Latin works from 1530 on he exclusively wrote chymia and chymista in describing activity that we today would characterize as chemical or alchemical. As

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1496-472: 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

1564-464: 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

1632-411: Is explained as meaning the "Egyptian art". The first occurrence of the word is said to be in a treatise of Julius Firmicus , an astrological writer of the 4th century, but the prefix al there must be the addition of a later Arabic copyist. In English, Piers Plowman (1362) contains the phrase "experimentis of alconomye", with variants "alkenemye" and " alknamye". The prefix al began to be dropped about

1700-457: Is housed in a 12.5-acre complex with state-of-the-art research laboratories. It has full-fledged working laboratories in physical chemistry , organic chemistry , inorganic chemistry , analytical chemistry and computer science . A video lecture facility is also available. The newly constructed Garden Campus of the university is spread over on more than 2000 Kanals of land having state of the art infrastructure, well equipped laboratories, one of

1768-537: 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

1836-400: Is sometimes called the central science because it provides a foundation for understanding both basic and applied scientific disciplines at 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

1904-468: 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

1972-458: 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

2040-507: 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,

2108-526: 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

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2176-509: 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

2244-455: 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

2312-421: The chemical elements that make up matter and compounds made of atoms , molecules and ions : their composition, structure, properties, behavior and 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

2380-493: 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

2448-469: 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. See diagram on electronic orbitals. In

2516-510: 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

2584-500: 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,

2652-529: 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

2720-438: 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

2788-481: The Department of Physical Education and Health and named as Department of Physical Education and Sports. Abdul Wali Khan University, Mardan establish partnerships with national as well as international universities, associations, institutes and academies and have signed a memorandum of understanding (MOUs or MoUs) with each. The following is the list of international collaborations. On 13 April 2017, Mashal Khan,

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2856-546: 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

2924-515: 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

2992-494: 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

3060-622: The biggest libraries of the region, computer labs, three hostels with a capacity of 1500 students, two on campus colleges, sports complex and many other facilities. Classes in the campus have been started. Tahdhīb al Afkārbiannual is the biannual Islamic studies research journal of Abdul Wali Khan University Mardan published in three different languages English, Urdu and Arabic. The university provides extra-curricular activities such as painting, articles, photography and sport. The students can participate through proper channels. The university provides facilities for many sports; they have been merged into

3128-412: 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

3196-495: The country and the colour "black" (Egypt was the "Black Land", by contrast with the "Red Land", the surrounding desert); so this etymology could also explain the nickname "Egyptian black arts". However, according to Mahn , this theory may be an example of folk etymology . Assuming an Egyptian origin, chemistry is defined as follows: Thus, according to Budge and others, chemistry derives from an Egyptian word khemein or khēmia , "preparation of black powder", ultimately derived from

3264-522: The early eighteenth century. In 16th, 17th and early 18th century English the spellings — both with and without the "al" — were usually with an i or y as in chimic / chymic / alchimic / alchymic . During the later 18th century the spelling was re-fashioned to use a letter e , as in chemic in English. In English after the spelling shifted from chimical to chemical , there was corresponding shift from alchimical to alchemical , which occurred in

3332-429: 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 ,

3400-444: 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

3468-445: 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:

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3536-473: 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 a definite composition and set of properties . A collection of substances

3604-456: The manuscripts, this word is also written khēmeia ( χημεία ) or kheimeia ( χειμεία ), which is the probable basis of the Arabic form. According to Mahn , the Greek word χυμεία khumeia originally meant "cast together", "casting together", "weld", "alloy", etc. (cf. Gk. kheein ( χέειν ) "to pour"; khuma ( χύμα ), "that which is poured out, an ingot"). Assuming a Greek origin, chemistry

3672-706: The middle of the 16th century (further details of which are given below). According to the Egyptologist Wallis Budge , the Arabic word al-kīmiyaʾ actually means "the Egyptian [science]", borrowing from the Coptic word for "Egypt", kēme (or its equivalent in the Mediaeval Bohairic dialect of Coptic, khēme ). This Coptic word derives from Demotic kmỉ , itself from ancient Egyptian kmt . The ancient Egyptian word referred to both

3740-527: The name khem , Egypt. A decree of Diocletian , written about 300 AD in Greek, speaks against "the ancient writings of the Egyptians, which treat of the khēmia transmutation of gold and silver". Arabic al-kīmiyaʾ or al-khīmiyaʾ ( الكيمياء or الخيمياء ), according to some, is thought to derive from the Koine Greek word khymeia ( χυμεία ) meaning "the art of alloying metals, alchemy"; in

3808-419: 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

3876-523: 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

3944-478: 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

4012-433: 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 ,

4080-544: 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

4148-695: The rich dark soil of the Nile river valley. There are two main views on the derivation of the Greek word. According to one, the word comes from the greek χημεία (chimeía), pouring, infusion, used in connexion with the study of the juices of plants, and thence extended to chemical manipulations in general; this derivation accounts for the old-fashioned spellings "chymist" and "chymistry". The other view traces it to khem or khame , hieroglyph khmi , which denotes black earth as opposed to barren sand, and occurs in Plutarch as χημία (chimía); on this derivation alchemy

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4216-403: 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

4284-474: 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

4352-645: 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

4420-695: 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

4488-421: 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

4556-507: The word is uncertain, but the Arabic term kīmiyāʾ ( كيمياء ) is likely derived from either the Ancient Greek word khēmeia ( χημεία ) or the similar khēmia ( χημία ). The Greek term khēmeia , meaning "cast together" may refer to the art of alloying metals, from root words χύμα (khúma, "fluid"), from χέω (khéō, "I pour"). Alternatively, khēmia may be derived from the ancient Egyptian name of Egypt , khem or khm , khame , or khmi , meaning "blackness", likely in reference to

4624-537: Was frequently re-published in the second half of the 16th century in Latin and was also published in a number of vernacular European languages, with the word spelled without the al- . In the 16th and 17th centuries in Europe the forms alchimia and chimia (and chymia ) were synonymous and interchangeable. The semantic distinction between a rational and practical science of chimia and an occult alchimia arose only in

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