alkali metals
most reactive metals; group 1A on the periodic table; all have 1 valence electron
alkaline earth metals
group 2A on the periodic table; all have 2 valence electrons
transition metals
Group B elements (middle of periodic table), valence electrons vary
inner transition metals
Separate rows on periodic table (actinides and lanthanides)
noble gases
group 8A on the periodic table; also known as the "inert" gases, NON-reactive, have full outer shell of electrons (He-full w/2 electrons, Ne-Rn full 8)
halogens
most reactive non-metals, group 7A on periodic table; all have 7 valence electrons
group
column on the periodic table, share similar physical and chemical properties
period or energy level
row on the periodic table
ionization energy
the energy required to remove a valence electron; is low for metals (easy to remove valence electrons) and high for non-metals (hard to remove valence electrons)
electronegativity
How strongly an atom attracts other electrons to itself in a chemical reaction
trend in atomic size
increases down a group, decreases across a period (left to right)
trend in ionization energy
decreases down a group (easier to remove electrons as you go down), increases across a period from left to right (harder to remove electrons as you move right).
trend in electronegativity
decreases down a group (atoms attract electrons more weakly as you go down), increases across a period (atoms attract electrons more strongly as you move towards the right).
valence electron
The electrons that are farthest away from the nucleus--in the outermost/highest energy level of an atom and are involved in chemical reactions.
Cation
When an atom loses an electron- atomic radius decreases
Anion
When an atom gains an electron- atomic radius increases
Francium (Fr)
most reactive metal on periodic table
Fluorine (F)
the most electronegative element on the periodic table
electron affinity
an elements attraction for its own electrons