2 The Periodic Table

Question 1

electronegativity trends

Answer 1

measure of attractive force that an atom will exert on an electron in a chemical bond

increases right and up on periodic table
EXCEPTION: noble gases

Question 2

ionization energy trends

Answer 2

energy required to remove electron from gaseous phase
endothermic process
multiple ionization energies as more electrons removed (higher each time)

increases right and up periodic table

Question 3

atomic radius

Answer 3

1/2 distance between centers of 2 atoms of an element briefly in contact

decreases right and up periodic table

Question 4

electron affinity

Answer 4

energy dissipated by gaseous species when it gains electron
exothermic process

increases right and up periodic table

Question 5

alkali metals (Group I)

Answer 5

metals
lower densities

low IE, EA, electronegativity
largest atomic radii of respective period

easily form univalent cations
react readily with nonmetals, especially halogens

Question 6

alkaline metals (Group II)

Answer 6

metals
increased Z(eff) --> decreased atomic radii

Question 7

chalcogens (Group 16)

Answer 7

nonmetals and metalloids
6 electrons in valence shell

increased ionic radii, decreased atomic radii

important biomolecules
high concentrations toxic/damaging

Question 8

halogens (Group 17)

Answer 8

highly reactive nonmetals
7 valence electrons

increased electronegativities, EAs

Question 9

noble gases (Group 18)

Answer 9

inert gases
filled valence shells
increased ionization energies
little to no electronegativity
low boiling points
gases at RT

Question 10

transition metals (Groups 3 - 12)

Answer 10

metals

lower EA, IE, electronegativity
high melting/boiling points

good conductors (loosely held electrons in d-orbitals of valence shell)

different positive oxidation states for different bonding