The Periodic Law
states that the elements, when listed in order of their atomic numbers (originally, atomic weights), fall into recurring groups, so that elements with similar properties occur at regular intervals
periodic law
any of the elements fluorine, chlorine, bromine, iodine, and astatine, in group 17 of the periodic table, reactive nonmetal elements that form strongly acidic compounds with hydrogen from which simple salts can be made
halogens
the energy required to remove one electron from a neutral atom of an element
ionization energy
_________ bonding results from the electrical attraction between cations and ions, whereas _________ bonding results from the sharing of electron pairs between two atoms
ionic, covalent
created by equal but opposite charges that are separated by a short distance
dipole
a table of the chemical elements arranged in order of atomic number, usually in rows, so that elements with similar atomic structure (and hence similar chemical properties) appear in vertical columns
periodic table
any of the elements lithium, sodium, potassium, rubidium, cesium, and francium, in Group 1 of the periodic table; very reactive
alkali metals
the energy change that occurs when an electron is acquired by a neutral atom
electron affinity
the ability of a substance to be hammered or beaten into thin sheets
malleability
the intermolecular force in which a hydrogen atom that is bonded to a highly electronegative atom is attracted to an unshared pair of electrons of an electronegative atom in a nearby molecule; very weak
hydrogen bonding
the 14 elements with atomic numbers from 58 to 71
lanthanides
any of the elements beryllium, magnesium, calcium, strontium, barium, and radium, in Group 2 of the periodic table; reactive
alkaline-earth metals
the electrons available to be lost, gained, or shared in the formation of chemical compounds
valence electron
the energy required to break a chemical bond and form neutral isolated atoms
bond energy
the intermolecular attractions resulting from the constant motion of electrons and the creation of instantaneous dipoles; found in almost all atoms and molecules
London dispersion forces
the 14 elements with atomic numbers from 90 to 103, all are radioactive
actinides
any of the set of metallic elements occupying a central block in the periodic table --> iron, manganese, chromium, and copper
transition elements
a measure of the ability of an atom in a chemical compound to attract electrons from another atom in the compound
electronegativity
a charged group of covalently bonded atoms
polyatomic ion
the mixing of two or more atomic orbitals of similar energies on the same atom to produce new hybrid atomic orbitals of equal energies
hybridization
credited for the development of the periodic table
Mendeleev
the elements located in the main eight columns on the periodic table --> groups 1-2 and 13-18
main-group elements
a ___________ is formed by the loss of one or more electrons (positive ion) whereas a ___________ is formed by the addition of one or more electrons (negative ion)
cation, anion
bonding in molecules or ions that cannot be correctly represented by a single Lewis structure
resonance
useful for explaining shapes of molecules
VSEPR theory