Studied by 0 people
____ created the first periodic table
Mendeleev
The first periodic table was based off of _____
atomic mass
The modern periodic table was created by _____.
Moseley
The modern periodic table is based off of _____
atomic number
Periodic Law
The physical and chemical properties of the elements are periodic functions of their atomic numbers
Periodic Table
an arrangement of the elements in order of their atomic numbers so that elements with similar properties fall in the same column, or group
Lanthanides
The 14 elements with atomic numbers from 58 to 71
Actinides
The 14 elements with atomic numbers from 90 to 103
Noble Gases
Group 18 elements
Period
horizontally in rows
Groups
Vertical columns
Alkali metals
The elements of Group 1 of the periodic table; soft enough to cut with a knife, very reactive, melts at low temperatures
Alkaline-Earth Metals
The elements of Group 2 of the periodic table; higher melting points, less reactive than alkali metals, harder, denser, stronger
Hydrogen
doesn’t share the same properties as Group 1 elements
Helium
possesses chemical stability unlike Group 2 elements
Transition metals
The d-block elements with typical metallic properties; less reactive than alkali metals and alkaline earth metals
Main Group Elements
The p-Block elements together with the s-Block elements
Halogens
The elements of Group 17; most reactive non-metals
Atomic radius
one-half the distance between the nuclei of identical atoms that are bonded together
Ion
an atom or group of bonded atoms that has a positive or negative charge
Ionization
Any process that results in the formation of an ion
Ionization Energy(IE)
The energy required to remove one electron from a neutral atom of an element
Ionization energies of the main group elements _____ across each period
increase
Among the main group elements, ionization generally ____ down the groups
decrease
Electron Affinity
the energy change that occurs when an electron is acquired by a neutral atom
Cation
a positive ion
Anion
a negative ion
Valence electrons
the electrons available to be lost, gained, or shared in the formation of chemical compounds
Electronegativity
a measure of the ability of an atom in a chemical compound to attract electrons from another atom in the compound
Electronegativities tend to _____ across each period
increase
Electronegativities tend to either ____ down a group or remain about the same
decrease
