Periodic Trends Flashcards
Period
Across
Group
Down
Valence electrons
From s or p sub level
Electrons in outer principle level
Transition metals: _ valence e
2
Most stable =
Unreactive
Ionization energy definition
Energy needed to remove an electron from outer shell
Trend for ionization energy
Period: increases because smaller atomic radius.
Group: decreases because size increases down a group, valence e are further from nucleus.
Electron affinity definition
How much an atom wants an additional electron
Electron affinity trend
Period : increases thru halogens and stops at noble gases bc valence e determine the need for electrons
Group: decreases, size increases and nucleus is farther from outer edge
Electronegativity definition
How much an atom attracts the electrons of a bond
Electronegativity
Period: increases through halogens and stops at noble gases , valence electrons determine the attraction of an electron in a bond
Group: decreases, increase in size and nucleus farther from where electrons are bonded.
