Note: This glossary is constantly being updated with new terms and definitions.
This glossary of basic chemistry definitions provides a quick reference to some of the most important terms in the field. The glossary is organized alphabetically, making it easy to find the term you are looking for. Each term is defined in clear and concise language, so you can quickly understand its meaning.
Jump to your required definitions from below alphabets (A to Z).
A
Actinium – Actinium is a chemical element with the symbol Ac and atomic number 89.
Aluminum – A chemical element with the symbol Al and atomic number 13, belonging to the group of post-transition metals. It is a lightweight, silvery-white metal that is highly ductile, malleable, and corrosion-resistant.
Americium – Americium is a synthetic chemical element with the symbol Am and atomic number 95.
Antimony – Antimony element is a chemical element with the symbol Sb and atomic number 51. It is a lustrous gray metalloid that is found in nature mainly as the sulfide mineral stibnite.
Argon – Argon is a chemical element with the symbol Ar and atomic number 18.
Arsenic – A chemical element with the symbol As and atomic number 33, belonging to the group of metalloids.
Astatine – Astatine is a chemical element with the symbol At and atomic number 85. It is a highly radioactive element.
Atom – The basic unit of a chemical element, consisting of a nucleus containing positively charged protons and uncharged neutrons, with negatively charged electrons orbiting around the nucleus.
B
Barium – Barium is a chemical element with the symbol Ba and atomic number 56, commonly used in various applications such as X-ray imaging and fireworks.
Berkelium – Berkelium is a synthetic chemical element with the atomic number 97 and the symbol Bk.
Beryllium – Beryllium is a chemical element with the symbol Be and atomic number 4.
Bismuth – Bismuth is a chemical element with the symbol Bi and atomic number 83, characterized as a brittle, silvery-white metal.
Bohrium – Bohrium is a chemical element with the atomic number 107 and symbol Bh.
Boiling point – The boiling point is the temperature at which a substance changes from its liquid state to its gaseous state, at a given pressure.
Bonding electrons – Electrons involved in the formation of a chemical bond between atoms.
Boron – A chemical element with the symbol B and atomic number 5. It is a metalloid with properties intermediate between those of metals and nonmetals.
Bromine – Bromine is a chemical element with the symbol Br and atomic number 35. It is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapor.
C
Cadmium – Cadmium is a soft, silvery-white metal with the symbol Cd and atomic number 48. It is chemically similar to the two other stable metals in group 12, zinc and mercury.
Cesium – Cesium is a chemical element with the symbol Cs and atomic number 55. It is a soft, silvery-gold alkali metal that is highly reactive and readily forms compounds.
Calcium – Calcium is a chemical element with the symbol Ca and atomic number 20.
Californium – Californium is a chemical element with the symbol Cf and atomic number 98.
Carbon – A chemical element with the symbol “C” and atomic number 6, occurring naturally in all living organisms and many minerals, and constituting the basis of organic chemistry.
Cerium – Cerium is a chemical element with the symbol Ce and atomic number 58, belonging to the lanthanide series of elements.
Chlorine – Chlorine is a chemical element with the symbol Cl and atomic number 17.
Chromium – A metallic chemical element with the atomic number 24 and symbol Cr. It is a hard, lustrous, steel-gray transition metal known for its corrosion resistance and high melting point.
Cobalt – A chemical element with the symbol Co and atomic number 27, known for its lustrous, silver-gray appearance and magnetic properties.
Combustion – A chemical reaction characterized by the rapid combination of a substance with oxygen, typically accompanied by the release of heat and light.
Compound – A substance formed by the chemical combination of two or more elements in definite proportions.
Conductivity – The measure of a material’s ability to conduct electric current, typically influenced by the movement of electrons within atoms or molecules.
Copernicium – Copernicium is a synthetic chemical element with the symbol Cn and atomic number 112.
Copper – A chemical element with the symbol Cu and atomic number 29, known for its reddish-brown color, high thermal and electrical conductivity, and malleability.
Covalent bonds – Covalent bonds are chemical bonds formed by the sharing of electron pairs between atoms.
Curium – Curium is a synthetic chemical element with the symbol Cm and atomic number 96.
D
Darmstadtium – Darmstadtium is a synthetic chemical element with the symbol Ds and atomic number 110.
Diatomic – Diatomic refers to a molecule composed of two atoms.
Dubnium – Dubnium is a synthetic chemical element with the symbol Db and atomic number 105.
Ductility – Ductility is the ability of a material, at the atomic level, to undergo plastic deformation without fracturing when subjected to tensile forces, resulting in the rearrangement of atoms and electrons within the material.
Duplet – A duplet refers to a set of two electrons occupying a stable electron configuration in the outermost energy level or shell of an atom.
Dysprosium – Dysprosium is a chemical element with the symbol Dy and atomic number 66, characterized as a rare-earth metal.
E
Einsteinium – Einsteinium is a synthetic chemical element with the symbol Es and atomic number 99.
Electronegativity – A measure of the tendency of an atom to attract a shared pair of electrons in a chemical bond.
Element – A fundamental substance that cannot be broken down into simpler substances by chemical means and is composed of atoms of the same atomic number.
Erbium – Erbium is a chemical element with the symbol Er and atomic number 68, belonging to the lanthanide series of elements.
Europium – Europium is a chemical element with the symbol Eu and atomic number 63, belonging to the lanthanide series of elements.
F
Fermium – Fermium is a synthetic chemical element with the symbol Fm and atomic number 100.
Flerovium – A synthetic chemical element with the atomic number 114 and symbol Fl.
Fluorine – Fluorine is a chemical element with the symbol F and atomic number 9.
Francium – Francium is a chemical element with the symbol Fr and atomic number 87.
G
Gadolinium – Gadolinium is a chemical element with the symbol Gd and atomic number 64, belonging to the lanthanide series of elements.
Gallium – A chemical element with the symbol Ga and atomic number 31, belonging to the group of post-transition metals.
Germanium – Germanium is a chemical element with the atomic number 32 and the symbol Ge.
Gold – Gold is a chemical element with the symbol Au and atomic number 79, characterized by its dense, soft, yellowish metal.
Group 1 – Group 1 of the periodic table refers to the first column of elements in the table, which consists of alkali metals.
Group 13 – Group 13 refers to the 13th group or column of elements in the periodic table of elements. It consists of the chemical elements boron (B), aluminum (Al), gallium (Ga), indium (In), and thallium (Tl).
Group 14 – Group 14 refers to the 14th group in the periodic table of elements, also known as the carbon group.
Group 15 – Group 15 refers to the nitrogen group on the periodic table of elements. It consists of the elements nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi).
Group 16 – Group 16, also known as Group VIA or the chalcogens, is a group of elements in the periodic table that includes oxygen (O), sulfur (S), selenium (Se), tellurium (Te), and polonium (Po).
Group 17 – Group 17 refers to the 17th group or column in the periodic table of elements, also known as the halogens. The group includes the elements fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).
Group 18 – Group 18 refers to the group of elements in the periodic table known as the noble gases or inert gases. The group includes helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn).
Group 2 – Group 2 refers to the second column of elements in the periodic table, also known as the alkaline earth metals.
H
Hafnium – Hafnium is a chemical element with the symbol Hf and atomic number 72, characterized as a shiny, silvery metal.
Hassium – Hassium is a synthetic chemical element with the symbol Hs and atomic number 108.
Helium – A chemical element with the symbol He and atomic number 2, belonging to the group of noble gases. It is the second lightest and second most abundant element in the universe.
Holmium – Holmium is a chemical element with the symbol Ho and atomic number 67, belonging to the lanthanide series of the periodic table.
Hydrogen – The first and lightest chemical element in the periodic table, with the symbol H and atomic number 1. It is the most abundant element in the universe and plays a crucial role in various chemical reactions.
I
Indium – Indium is a chemical element with the symbol In and atomic number 49. It is a post-transition metal that makes up 0.21 parts per million of the Earth’s crust.
Iodine – Iodine element is a non-metallic, lustrous, deep purple-black solid with the symbol “I” and atomic number 53. It is the heaviest of the stable halogens.
Ionization energy – The ionization energy is the minimum amount of energy required to remove an electron from a neutral atom or ion in its ground state.
Iridium – Iridium is a chemical element with the symbol Ir and atomic number 77, known for its dense, corrosion-resistant properties and its use in various applications, including electronics and catalysis.
Iron – A chemical element with the symbol Fe and atomic number 26, characterized by its lustrous silvery-gray appearance, high tensile strength, and ability to easily be magnetized.
Isotope – One or more forms of an element that have the same number of protons but different numbers of neutrons.
J
K
Krypton – Krypton is a chemical element with the symbol Kr and atomic number 36. It is a colorless, odorless, tasteless noble gas that occurs in trace amounts in the atmosphere and is often used with other rare gases in fluorescent lamps. Krypton is chemically inert.
L
Lanthanum – Lanthanum is a chemical element with the symbol La and atomic number 57, belonging to the group of rare earth elements.
Lawrencium – Lawrencium is a chemical element with the symbol Lr and atomic number 103.
Lead – The chemical element lead (Pb) is a heavy metal with atomic number 82, known for its bluish-white color, high density, and toxic properties.
Lewis structure – A Lewis structure, also known as a Lewis dot structure or electron dot structure, is a diagrammatic representation of the arrangement of atoms and valence electrons in a molecule or ion.
Lithium – A chemical element with the symbol Li and atomic number 3, belonging to the alkali metal group. It is a soft, silvery-white metal that is highly reactive and is the lightest solid element at room temperature.
Livermorium – Livermorium is a synthetic chemical element with the atomic number 116 and the symbol Lv.
Lutetium – Lutetium is a chemical element with the symbol Lu and atomic number 71, belonging to the lanthanide series of the periodic table.
M
Magnesium – Magnesium is a chemical element with the symbol Mg and atomic number 12.
Malleability – The property of a substance, particularly metals, to be capable of being shaped or deformed by external forces, such as hammering, without breaking, due to the ability of its atoms or electrons to move and rearrange while maintaining cohesion.
Manganese – A chemical element with the symbol Mn and atomic number 25, characterized as a hard, brittle, gray-white metal. It is a transition metal and is commonly used in the production of steel and other alloys.
Meitnerium – Meitnerium is a synthetic chemical element with the symbol Mt and atomic number 109.
Melting point – The melting point is the temperature at which a substance changes from a solid state to a liquid state at a given pressure.
Mendelevium – Mendelevium is a synthetic chemical element with the symbol Md and atomic number 101.
Mercury – Mercury is a chemical element with the symbol Hg and atomic number 80, characterized by its silvery appearance and liquid state at room temperature.
Mineral – A naturally occurring inorganic solid substance with a definite chemical composition and crystalline structure.
Mixture – A combination of two or more substances that are not chemically bonded and can be separated by physical means.
Molecule – A molecule is a group of two or more atoms held together by chemical bonds, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction.
Molybdenum – Molybdenum element is a chemical element with the symbol Mo and atomic number 42. It is a silvery-gray metal with a high melting point and low coefficient of thermal expansion. Molybdenum is used in a variety of applications, including steel alloys, catalysts, and electronics.
Monatomic – Monoatomic gas refers to a gaseous state where each particle is composed of a single atom.
Moscovium – A synthetic chemical element with the atomic number 115 and the symbol Mc. It belongs to the group 15 of the periodic table and is named after Moscow Oblast in Russia.
N
Neodymium – Neodymium is a chemical element with the symbol Nd and atomic number 60, characterized as a silvery metal that belongs to the lanthanide series of elements.
Neon – A chemical element with the atomic number 10 and the symbol Ne, belonging to the noble gases group. It is a colorless, odorless, and inert gas.
Neptunium – Neptunium is a chemical element with the symbol Np and atomic number 93.
Nickel – A chemical element with the symbol Ni and atomic number 28, characterized as a hard, silvery-white metal with a high melting point and excellent corrosion resistance.
Nihonium – Nihonium is a synthetic chemical element with the symbol Nh and atomic number 113.
Niobium – Niobium element is a chemical element with the symbol Nb and atomic number 41. It is a light gray, crystalline, and ductile transition metal.
Nitrogen – A chemical element with the symbol N and atomic number 7. It is a colorless, odorless, and tasteless gas that makes up about 78% of Earth’s atmosphere.
Nobelium – Nobelium is a synthetic chemical element with the symbol No and atomic number 102.
Nonbonding electrons – Electrons in an atom or molecule that are not involved in chemical bonding.
O
Oganesson – Oganesson is a synthetic chemical element with the symbol Og and atomic number 118.
Orbit – A specific path or region in which an electron revolves around the nucleus of an atom.
Osmium – Osmium is a chemical element with the symbol Os and atomic number 76, known for its high density and blue-white color.
Oxygen – A chemical element with the symbol O and atomic number 8, commonly found in the Earth’s atmosphere and essential for respiration and combustion.
P
Palladium – Palladium element is a chemical element with the symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by the English chemist William Hyde Wollaston.
Periodic table – The periodic table is a tabular arrangement of chemical elements, organized based on their atomic number, electron configuration, and recurring chemical properties.
Phosphorus – A chemical element with the symbol P and atomic number 15. It is a nonmetallic element that belongs to the nitrogen group of elements on the periodic table.
Platinum – Platinum is a chemical element with the symbol Pt and atomic number 78, known for its dense, malleable, and corrosion-resistant properties.
Plutonium – A radioactive, silvery-white metallic chemical element with the atomic number 94, symbol Pu, and atomic weight 244, primarily used in nuclear reactors and the production of nuclear weapons.
Polonium – Polonium is a chemical element with the symbol Po and atomic number 84, known for its highly radioactive and toxic properties.
Potassium – A chemical element with the symbol K and atomic number 19. It is a soft, silvery-white alkali metal that belongs to Group 1 of the periodic table.
Praseodymium – Praseodymium is a chemical element with the symbol Pr and atomic number 59, belonging to the lanthanide series.
Promethium – Promethium is a chemical element with the symbol Pm and atomic number 61, belonging to the lanthanide series.
Protactinium – Protactinium is a chemical element with the symbol Pa and atomic number 91.
Q
R
Radium – A highly radioactive chemical element with the symbol Ra and atomic number 88.
Radon – Radon is a chemical element with the symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, and tasteless gas.
Reactivity – The capacity of a substance or system to undergo a chemical reaction.
Rhenium – Rhenium is a chemical element with the symbol Re and atomic number 75, known for its high melting point and resistance to corrosion.
Rhodium – Rhodium element is a rare, silvery-white, hard, corrosion-resistant transition metal with the symbol Rh and atomic number 45. It is a member of the platinum group.
Roentgenium – A synthetic chemical element with the symbol Rg and atomic number 111.
Rubidium – Rubidium is a chemical element with the symbol Rb and atomic number 37. It is a soft, silvery-white metal that is highly reactive with water and oxygen.
Ruthenium – Ruthenium is a chemical element with the symbol Ru and atomic number 44. It is a member of the platinum group of metals, and is found in nature as a minor component of platinum ores.
Rutherfordium – Rutherfordium is a chemical element with the symbol Rf and atomic number 104.
S
Samarium – Samarium is a chemical element with the symbol Sm and atomic number 62, belonging to the lanthanide series of elements.
Scandium – Scandium is a chemical element with the symbol Sc and atomic number 21.
Seaborgium – Seaborgium is a synthetic chemical element with the symbol Sg and atomic number 106.
Selenium – Selenium (Se) is a chemical element with the symbol Se and atomic number 34.
Silicon – A chemical element with the atomic number 14 and symbol Si, belonging to the group of metalloids in the periodic table.
Silver – Silver element is a chemical element with the symbol Ag and atomic number 47. It is a soft, white, lustrous transition metal that exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal.
Sodium – A chemical element with the symbol Na and atomic number 11, characterized by its silvery-white metallic appearance and highly reactive nature.
Strontium – Strontium is a chemical element with the symbol Sr and atomic number 38. It is an alkaline earth metal that is soft, silvery-white, and highly reactive.
Sulfur – A chemical element with the symbol S and atomic number 16, characterized by a yellow color, brittle texture, and a distinctive odor when in its elemental form.
T
Tantalum – Tantalum is a chemical element with the symbol Ta and atomic number 73, known for its high melting point and corrosion resistance.
Technetium – Technetium (Tc) is a chemical element with the atomic number 43. It is the lightest element whose isotopes are all radioactive. All available technetium is produced as a synthetic element.
Tellurium – Tellurium element is a brittle, mildly toxic, rare, silver-white metalloid. It is chemically related to selenium and sulfur, all three of which are chalcogens.
Tennessine – A hypothetical super-heavy chemical element with the atomic number 117 and symbol Ts. It is named after the state of Tennessee in the United States.
Terbium – Terbium is a chemical element with the symbol Tb and atomic number 65, belonging to the lanthanide series of elements.
Thallium – Thallium is a chemical element with the symbol Tl and atomic number 81, belonging to the group of post-transition metals.
Thorium – Thorium is a naturally occurring radioactive chemical element with the symbol Th and atomic number 90.
Thulium – Thulium is a chemical element with the symbol Tm and atomic number 69, belonging to the lanthanide series of elements on the periodic table.
Tin – Tin element is a chemical element with the symbol Sn and atomic number 50. It is a soft, silvery-white metal with a bluish tinge.
Titanium – A chemical element with the atomic number 22 and symbol Ti, known for its low density, high strength, and corrosion resistance.
Tungsten – Tungsten is a chemical element with the symbol W and atomic number 74, known for its high melting point and density.
U
Uranium – A naturally occurring, radioactive chemical element with the symbol U and atomic number 92.
V
Valence electrons – Electrons located in the outermost energy level (valence shell) of an atom that participate in chemical bonding.
Vanadium – Vanadium is a chemical element with the symbol V and atomic number 23.
W
X
Xenon – Xenon is a chemical element with the symbol Xe and atomic number 54. It is a colorless, odorless noble gas found in Earth’s atmosphere in trace amounts.
Y
Ytterbium – Ytterbium is a chemical element with the symbol Yb and atomic number 70, belonging to the lanthanide series of elements.
Yttrium – Yttrium is a silvery-metallic transition metal chemically similar to the lanthanides and has often been classified as a “rare-earth element”.
Z
Zinc – A chemical element with the symbol Zn and atomic number 30. It is a bluish-white metal that is commonly used in alloys, such as brass, and is known for its corrosion resistance.
Zirconium – Zirconium element is a chemical element with the symbol Zr and atomic number 40. It is a lustrous, grayish-white, soft, ductile, malleable metal that is solid at room temperature.
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