A figure, named after Italian physicist Amedeo Avogadro (1776-1856), equal to 6.022137 × 10 23 . Avogadro's number indicates the number of molecules in a mole.
The energy required to pull apart the atoms in a chemical bond.
The joining, through electromagnetic force, of atoms representing different elements.
A substance made up of atoms of more than one element. These atoms are usually joined in molecules.
A type of chemical bonding in which two atoms share valence electrons.
A term describing an element that exists as molecules composed of two atoms.
A form of intermolecular bonding between molecules formed by a polar covalentbond.
A negatively charged particle in an atom.
The relative ability of an atom to attract valence electrons.
A chemical formula that shows the smallest possible whole-number ratio of the atoms involved. Compare with molecular formula and structural formula.
A kind of dipole-dipole attraction between molecules formed of hydrogen along with an element having a high electronegativity.
The bonding that exists between molecules. This is not to be confused with chemical bonding, the bonding of atoms within a molecule.
An atom or group of atoms that has lost or gained one or more electrons, and thus has a net electric charge.
A form of chemical bonding resulting from attractions between ions with opposite electric charges.
Substances having the same chemical formula, but which are chemically dissimilar due to differences in the arrangement of atoms.
A term describing the weak intermolecular bond between molecules that are not formed by a polar covalent bond.
The SI fundamental unit for "amount of substance." A mole is, generally speaking, Avogadro's number of molecules; however, in the more precise SI definition, a mole is equal to the number of carbon atoms in 12.01 g of carbon.
A chemical formula that indicates the types and numbers of atoms involved, showing the actual proportions of atoms in a molecule. Compare with empirical formula and structural formula.
A form of crystalline solid—a solid in which the constituent parts have a simple and definite geometric arrangement repeated in all directions—in which the molecules have a neutral electric charge. Table sugar (sucrose) is an example.
A group of atoms, usually but not always representing more than one element, joined in a structure. Compounds are typically made up of molecules.
A term describing the distribution of valence electrons that takes place in chemical bonding for most elements, which end up with eight valence electrons.
The type of chemical bonding between atoms that have differing values of electronegativity. Water molecules are an example of a polar covalent bond.
The orbital pattern of the valence electrons at the outside of an atom.
The area of chemistry devoted to the three-dimensional arrangement of atoms in a molecule.
A diagram that shows how the atoms are bondedtogether, complete with lines representing covalent bonds. Compare with empirical formula and molecular formula.
Electrons that occupy the highest energy levels in anatom. These are the only electrons involved in chemical bonding.
The property of the atom of one element that determines its ability to bond with atoms of other elements.
A means of representing the three-dimensional structure of atoms in a molecule.
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