Question | Answer |
Dmitri Mendeleev | organized the first periodic table of elements |
Lothar Myer | organized one of the first periodic tables of elements (around the same time as Mendeleev, however Mendeleev’s was published first) |
Periodic law | the properties of the elements are periodic functions of their atomic numbers |
Periodic table | display of the elements in order of atomic number with similar elements falling into columns |
Noble Gas | the column of elements from helium to radon (inert gases) |
Lanthanides | the row of elements beneath the periodic table, from cerium to lutetium; also called rare earths |
Actinides | the row of elements below the periodic table, from thorium to lawrencium |
Periodicity | regular periodic variations of properties of elements with atomic number (and position in the periodic table) |
Period | the elements in a horizontal row of the periodic table (series) |
Family | a vertical column in the periodic table (group) |
Series | the elements in a horizontal row of the periodic table (period) |
Group | a vertical column in the periodic table (family) |
s-block elements | elements in groups one-two (excluding H) |
p-block elements | elements in groups thirteen-eighteen (excluding He) |
d-block metals | elements in groups three-12 |
f-block metals | elements 58-71 and 90-103 |
Alkali metals | the metal in the first column of the periodic table |
Alkaline Earth metals | elements in the second column of the periodic table all fall into this series |
metal | elements that form cations when compounds of it are in solution and oxides of the elements form hydroxides rather than acids in water |
transition metals | the three rows of elements in the middle of the periodic table, from scandium to mercury |
main-group or representative elements | an element in the s-block or p-block |
halogens | the reactive nonmetals that are in Group 17 of the periodic table; all of these are electronegative |
atomic radius | radius of an atom; ½ the distance between two adjacent atoms in crystals of elements |
bonding radius | the distance between two bonded atoms |
ionization energy | the minimum amount of energy required to remove the most loosely held electron of an isolated gaseous atom or ion |
electron affinity | how much something wants to pick up electrons; the amount of energy absored in the process in which an electron is added to a neutral isolated gaseous atom to form a gaseous ion with a 1-charge |
valance electron | an electron that is available to be lost, gained, or shared in the formation of chemical compounds |
cation | a positive ion |
anion | a negative ion |
ion | an atom or group of bonded atom that has a positive or negative charge |
atomic mass unit | a unit of mass that is exactly 1/12 the mass of a carbon-12 atom, or 1.660540 x 10-27 kg |
nonmetal | an element that is a poor conductor of heat and electricity |
isotope | atoms of the same element that have different masses |
shielding effect | radiation-absorbing material that is used to decrease radiation exposure from nuclear reactors |