Hiedel Honors

14 elements with atomic numbers 58 to 71
14 elements with atomic numbers form 90 to 103
Rare Earth Elements/ INner-Transition Elements (f-block)
28 elements in the lathaninde and actinide periods they are shiny metal that are too reactive to be found as free elements; all are radioactive
periodic law
physical and chemical properties of the elements are periodic functions of their atomic number
periodic table
arrangement of elements in order of their atomic numbers so that elements with similar properties fall in the same column
alkali metals
elements in group 1 al have silvery appearance and are soft; very reactive so not ofuond on earth as free elements
alakli earth metals
elements in group 2 harder and more dense than group 1 but still are very reactive and not found on earth as free elements
group 17 most reactive non-metals
main group elements
p-block and s-block elements
transition elements
d-block elements; metals
a negative ion formed by the addition of one or more electrons leads to an increase in atomic radius
atomic radius
one-half the distance between the nucleus’ of two identical atoms that are bonded
a positive ion formed by the loss of one or more electron
electron affinity
energy change that occurs when an electron is gained by a neutral atom
measure of the ability of an atom in a chemical compound to attract electrons form another atom in the compound
atom or group of nonded atoms that have a positive or negative charge
any process that results in the formation of an ion
ionization energy
energy required to remove one electron form a neutral atom
valence electrons
electron available to be lost gained or shared int he formation of chemical compounds
chemical bond
mutual electrical attraction between the nuclui and valence electrons of different atoms that bind the atoms together
covalent bond
results from the sharing of electon pairs between two atoms
ionic bonding
chemical bonding that results from the electrical attraction between cations and anion
non-polar bond
bonding electrons are shared equally by the bonded atoms results in a balanced distribution of electrical charge
uneven distribution of charge
polar covalent bond
covalent bonded atoms have an unequal attraction for the shared electrons
bond energy
energy required to break a chemical bonds and form neutral isolated atoms
bond length
two bonded atoms at their minimum PE or the average distance between two bonded atoms
double bond
covalent bond in which two pairs of electrons are shared between two atoms
octet rule
chemical compounds tend to forms so that by gaining, losing, or sharing, an electron it has an octet of electrons in its highest occupied energy level
ionic compound
composed of positive and negative ions that are combined so that the numbers if positve and negative charges are equal
london dispersion forces
intermolecular attractions resulting from the constant motions of electrons and the creation of instaneous dipoles
V.S.E.P.R. Theory
staes that repulsion between the sets of valence-level electrons surronding an atom causes these sets to be oriented as far apart as possible