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This page is a glossary of chemistry terms. Chemistry has an extensive vocabulary and a significant amount of jargon. This is a list of chemical terms, including laboratory tools, glassware, and equipment. Chemistry itself is a physical science concerned with the composition, structure, and properties of matter, as well as the changes it undergoes during chemical reactions.

Note: All periodic table references refer to the IUPAC Style of the Periodic Table


An atom, with protons, neutrons, and electrons labelled



An example of combustion



Microcentrifuge or Eppendorf tube with Coomassie Blue solution
  • earth metal – see alkaline earth metal
  • electrolyte – a solution that conducts a certain amount of current and can be split categorically as weak and strong electrolytes
  • electrochemical cell – using a chemical reaction's current, electromotive force is made
  • electromagnetic radiation – a type of wave that can go through vacuums as well as material and classified as a self-propagating wave
  • electromagnetism – fields that have electric charge and electric properties that change the way that particles move and interact
  • electromotive force – a device that gains energy as electric charges pass through it
  • electron – a subatomic particle with a net charge that is negative
  • electron shells – an orbital around the atom's nucleus that has a fixed number electrons (usually two or eight)
  • electric charge – a measured property (coulombs) that determine electromagnetic interaction
  • element – an atom that is defined by its atomic number
  • energy – A system's ability to do work
  • enthalpy – measure of the total energy of a thermodynamic system (usually symbolized as H)
  • enthalpy of fusion -
  • entropy – the amount of energy not available for work in a closed thermodynamic system (usually symbolized as S)
  • enzyme – a protein that speeds up (catalyses) a reaction
  • Empirical formula – also called the simplest formula, gives the simplest whole -number ratio of atoms of each element present in a compound.
  • Equilibrium – Universally, it is the condition of a system in which all competing influences are balanced. Chemical equilibrium is the state in which the concentrations of the reactants and products have stopped changing in time.
  • eppendorf tube – generalized and trademarked term used for a type of tube; see microcentrifuge
  • exothermic process -
  • extrinsic property -


It represents 1 mol of electrons, or the Avogadro number of electrons: 6.022 × 1023 electrons. F = 96 485.339 9(24) C/mol


  • Galvanic cell – battery made up of electrochemical with two different metals connected by salt bridge
  • gas – particles that fill their container though have no definite shape or volume
  • Gay-Lussac's Law – The expression Gay-Lussac's law is used for each of the two relationships named after the French chemist Joseph Louis Gay-Lussac and which concern the properties of gases, though it is more usually applied to his law of combining volumes
  • geochemistry – the chemistry of and chemical composition of the Earth
  • Gibbs energy – value that indicates the spontaneity of a reaction (usually symbolized as G)
  • "gram-atom"-one gram atom of an element means collection of 6.023X10^23 atoms
  • group – the elements in a column of the periodic table. A family of elements



  • ideal gas -
  • ideal gas law – the volume of a gas is proportional to the amount of gas and its Kelvin temperature and inversely proportional to its pressure
  • independent variable -
  • indicator – a special compound added to solution that changes color depending on the acidity of the solution; different indicators have different colors and effective pH ranges
  • induced radioactivity – radioactivity caused by bombarding a stable isotope with elemental particles, forming a radioactive isotope
  • inorganic compound – compounds that do not contain carbon, though there are exceptions (see main article)
  • inorganic chemistry – a part of chemistry concerned with inorganic compounds
  • IUPAC – International Union of Pure and Applied Chemistry
  • insulator – material that resists the flow of electric current
  • intermediate -
  • intermolecular force -
  • intrinsic property -
  • ion – a molecule that has gained or lost one or more electrons
  • ionic bond – electrostatic attraction between oppositely charged ions
  • ionization -The breaking up of a compound into separate ions.


  • Joule – The SI unit of energy, defined as a newton-meter.


  • kelvin – A unit of measure for temperature based upon an absolute scale.
  • ketone – an organic compound with a carbonyl group between two carbon atoms
  • Kinetics – A sub-field of chemistry specializing in reaction rates
  • Kinetic energy – The energy of an object due to its motion.




  • natural abundance -
  • neat – conditions with a liquid reagent or gas performed with no added solvent or cosolvent
  • neutron – a neutral unit or subatomic particle that has no net charge
  • neutrino – a particle that can travel at speeds close to the speed of light and are created as a result of radioactive decay
  • nucleus – the centre of an atom made up of neutrons and protons, with a net positive charge
  • noble gases – group 18 elements, those whose outer electron shell is filled
  • non-metal – an element which is not metallic
  • nuclear – of or pertaining to the atomic nucleus
  • nuclear magnetic resonance spectroscopy – technique that exploits the magnetic properties of certain nuclei, useful for identifying unknown compounds
  • number density – a measure of concentration of countable objects (atoms, molecules, etc.) in space; number per volume



  • pH – the measure of acidity (or basicity) of a solution
  • passivation
  • plasma – state of matter similar to gas in which a certain portion of the particles are ionized
  • other metal – metallic elements in the p-block, characterized by having a combination of relatively low melting points (all less than 950 K) and relatively high electronegativity values (all more than 1.6, revised Pauling)
  • potential energy – energy stored in a body or in a system due to its position in a force field or due to its configuration
  • precipitate – formation of a solid in a solution or inside another solid during a chemical reaction or by diffusion in a solid
  • precision – How close the results of multiple experimental trials are. See also accuracy.
  • photon – a carrier of electromagnetic radiation of all wavelength (such as gamma rays and radio waves)
  • proton – a positive unit or subatomic particle that has a positive charge
  • protonation – the addition of a proton (H+) to an atom, molecule, or ion


  • quantum mechanics – the study of how atoms, molecules, subatomic particles, etc. behave and are structured
  • quarks – elementary particle and a fundamental constituent of matter
  • quanta- It is the minimum amount of bundle of energy



  • s-block elements – Group 1 and 2 elements (alkali and alkaline metals), which includes Hydrogen and Helium
  • salts – ionic compounds composed of anions and cations
  • salt bridge – devices used to connection reduction with oxidation half-cells in an electrochemical cell
  • saline solution – general term for NaCl in water
  • Schrödinger equation – quantum state equation which represents the behaviour of an election around an atom
  • semiconductor – an electrically conductive solid that is between a conductor and an insulator
  • serial dilution -
  • single bond – sharing of one pair of electrons
  • sol – a suspension of solid particles in liquid. Artificial examples include sol-gels.
  • solid – one of the states of matter, where the molecules are packed close together, there is a resistance of movement/deformation and volume change; see Young's modulus
  • solute – the part of the solution that is mixed into the solvent (NaCl in saline water)
  • solution – homogeneous mixture made up of multiple substances. It is made up of solutes and solvents.
  • solvent – the part of the solution that dissolves the solute (H2O in saline water)
  • spectrochemistry -
  • spectroscopy – study of radiation and matter, such as X-ray absorption and emission spectroscopy
  • speed of light – the speed of anything that has zero rest mass (Energyrest = mc² where m is the mass and c is the speed of light)
  • Standard conditions for temperature and pressure or SATP – a standardisation used in order compare experimental results (25 °C and 100.000 kPa)
  • state of matter – matter having a homogeneous, macroscopic phase; gas, plasma, liquid, and solid are the most well known (in increasing concentration)
  • structural formula -
  • sublimation – a phase transition from solid to limewater fuel or gas
  • subatomic particles – particles that are smaller than an atom; examples are protons, neutrons and electrons
  • substance – material with definite chemical composition


Phase diagram showing the triple and critical points of a substance
  • talc – a mineral representing the one on the Mohs Scale and composed of hydrated magnesium silicate with the chemical formula H2Mg3(SiO3)4 or Mg3Si4O10(OH)2
  • temperature – the average energy of microscopic motions of particles
  • theoretical yield – see yield
  • theory – a model describing the nature of a phenomenon
  • thermal conductivity – a property of a material to conduct heat (often noted as )
  • thermochemistry – the study of absorption/release of heat within a chemical reaction
  • thermodynamics – the study of the effects of changing temperature, volume or pressure (or work, heat, and energy) on a macroscopic scale
  • thermodynamic stability – when a system is in its lowest energy state with its environment (equilibrium)
  • thermometer – device that measures the average energy of a system
  • titration – the process of titrating one solution with another, also called volumetric analysis
  • torr – a unit to measure pressure (1 Torr is equivalent to 133.322 Pa or 1.3158×10−3 atm)
  • transition metal – elements that have incomplete d sub-shells, but also may be referred to as the d-block elements
  • transuranic element – element with atomic number greater than 92; none of the transuranic elements are stable
  • triple bond – the sharing of three pairs of electrons within a covalent bond (example N2)
  • triple point – the place where temperature and pressure of three phases are the same (Water has a special phase diagram)
  • Tyndall effect – the effect of light scattering by colloidal (mixture where one substance is dispersed evenly through another) or suspended particles


  • UN number – a four digit code used to note hazardous and flammable substances
  • uncertainty – a characteristic that any measurement that involves estimation of any amount cannot be exactly reproducible
  • uncertainty principle – knowing the location of a particle makes the momentum uncertain, while knowing the momentum of a particle makes the location uncertain
  • unit cell – the smallest repeating unit of a lattice
  • unit factor – statements used in converting between units
  • universal or ideal gas constant – proportionality constant in the ideal gas law (0.08206 L·atm/(K·mol))


  • valence electron – the outermost electrons of an atom, which are located in electron shells
  • Valence bond theory – a theory explaining the chemical bonding within molecules by discussing valencies, the number of chemical bonds formed by an atom
  • valency – The combining capacity of an element.
  • van der Waals force – one of the forces (attraction/repulsion) between molecules
  • van 't Hoff factor – ratio of moles of particles in solution to moles of solute dissolved
  • vapor – when a substance is below the critical temperature while in the gas phase
  • vapour pressure – pressure of vapour over a liquid at equilibrium
  • vaporization – phase change from liquid to gas
  • viscosity – the resistance of a liquid to flow (oil)
  • volt – one joule of work per coulomb – the unit of electrical potential transferred
  • voltmeter – instrument that measures the cell potential
  • volumetric analysis – see titration


  • water – H2O – a chemical substance, a major part of cells and Earth, and covalently bonded
  • wave function – a function describing the electron's position in a three-dimensional space
  • work – the amount of force over distance and is in terms of joules (energy)


  • X-ray – form of ionizing, electromagnetic radiation, between gamma and UV rays
  • X-ray diffraction – a method for establishing structures of crystalline solids using singe wavelength X-rays and looking at diffraction pattern
  • X-ray photoelectron spectroscopy – a spectroscopic technique to measure composition of a material


  • yield – the amount of product produced during a chemical reaction


  • zone melting – a way to remove impurities from an element by melting it and slowly travel down an ingot (cast)
  • Zwitterion – is a chemical compound whose net charge is zero and hence is electrically neutral. But there are some positive and negative charges in it, due to the formal charge, owing to the partial charges of its constituent atoms.
  • zinc-an element or a metal with symbol Zn

See also

External links