2 - Periodic Table Flashcards
Who made the first periodic table?
Dmitri Mendeleev, based on atomic weight
Who made the current version of the periodic table
Henry Moseley, based on atomic number
Periodic law
The chemical and physical properties of the elements are dependent in a periodic way upon their atomic number
Periods are ___ and groups are ___
Row; column
Characteristics of valence electrons
Greatest potential energy due to being far from the nucleus
What are representative elements
Groups 1,2,13-18
Nonrepresentative elements
Transition metals, lanthanide, actinide
All metals are ____ and ___ but not ___ because ____.
Lustrous; solids; mercury; liquid at standard conditions
General characteristics of metals
Shiny, solid (except mercury), high mp and densities (except lithium), malleable, ductile
low effective nuclear charge, low EN, large atomic radius, small ionic radius, low ionization energy, low electron affinity
Malleability
Ability to be hammered into shapes
Ductility
Ability to be pulled into wires
What are transition metals good conductor for
Good conductors of heat and electricity
Nonmetal characteristics
Brittle as solid, not really lustrous
High ionization energy, electron affinity, EN, small atomic radius, large ionic radii
Poor conductors of heat and electricity
Another name for metalloids
Semimetals
What elements are metalloids
B, Si, Ge(rmanium), As(arsenic), Sb(antimony), Te, Po(lonium), At(astatine)
What is Zeff and the trend
Effective nuclear charge - measures net positive charge experienced by valence electrons
Increases left —> right because atoms get a little smaller left to right
Each added proton pulls outer electrons stronger
How to find atomic radius
Half the distance between 2 nuclei briefly in contact with each other
What is trend of ionic radii of metalloids
Posses larger ionic radius than “real” nonmetals
Nonmetals gain electrons while nuclei maintain the same charge to achieve noble gas electron configuration
Ionic radius definition
Distance from nucleus to the outermost electrons in an ion (not necessarily valence electrons)
Ionic radii trend for metals close to metalloid line
Smaller ionic radius
More electrons to lose to achieve noble gas configuration
