The Periodic Table

Question 1

periodic law

Answer 1

states that the chemical and physical properties of the elements are dependent, in a periodic way, upon their atomic numbers

Question 2

periods

Answer 2

rows of the periodic table; represent the principal quantum numbers n=1 through n=7 for the s- and p- block elements

Question 3

groups

Answer 3

columns of the periodic table; contain elements that have the same electronic configuration in their valence shell

Question 4

A elements (representative elements)

Answer 4

have their valence electrons in the orbitals of either s or p shells; i.e. Group VA has five valence electrons with configuration s2p3

Question 5

B elements (nonrepresentative elements)

Answer 5

include both the transition elements and lanthanide and actinide series

Question 6

transition elements

Answer 6

have valence e- in the s and d shells

Question 7

lanthanide and actinide series

Answer 7

have their valence e- in s and f subshells

Question 8

metals

Answer 8

found on the left side and in the middle of the periodic table; lustrous (shiny) solids

Question 9

metal properties

Answer 9

malleable: ability to be hammered into shapes
ductility: ability to be drawn into wires
- low effective nuclear change, low electronegativity, large atomic radius, small ionic radius, low ionization energy, low electron affinity

Question 10

oxidation states

Answer 10

charges when forming bonds with other atoms; many transition metals have a multiple

Question 11

conductors

Answer 11

metals are good conductors easily conduct heat and electricity because their valence electrons are only loosely held on

Question 12

metal valence electrons

Answer 12

active metals: found in s subshell
transition metals: found in s and d subshell
lanthanide and actinide series: s and f subshells

Question 13

nonmetals

Answer 13

found predominantly in the upper right side of the periodic table

Question 14

properties of nonmetals

Answer 14

• generally brittle in solid state
• show little to no metallic luster
• high ionization energies, electron affinities, electronegativies as well as small atomic radii and large ionic radii
• poor conductors
• do not easily give up electrons

Question 15

metalloids (semimetals)

Answer 15

• share some characteristics with metals and nonmetals
• physical properties vary widely
• dependent on the elements with which they are reacting

Question 16

effective nuclear charge (Zeff)

Answer 16

electrostatic attraction between valence shell electrons and the nucleus; increases as you move from left to right within the same period; more or less constant within a group

Question 17

principal quantum number

Answer 17

increases by one each time as one moves down the elements of a given group; valence electrons are further away and held less tightly as this increases

Question 18

octet rule

Answer 18

elements tend to be most stable with eight electrons in their valence shell; many exceptions

Question 19

atomic radii trends

Answer 19

-decrease the more right and high up you are

Question 20

ionic radii

Answer 20

• metals lose electrons and become pos, nonmetals gain electrons and become negative
• metalloids can go in either direction but tend to follow the trend depending on what side of the line they fall on
• nonmetals close to metalloids possess a larger ionic radius
• metals close to metalloid line have a smaller ionic radius

Question 21

Ionization energy (IE)

Answer 21

energy required to remove an electron from a gaseous species; endothermic process

Question 22

endothermic process

Answer 22

requires input of heat

Question 23

ionization energy trends

Answer 23

-increases from left to right across a period and from bottom to top in a group

Question 24

first ionization energy

Answer 24

energy necessary to remove first electron, forming X+

Question 25

second ionization energy

Answer 25

energy necessary to remove second electron forming X2+

Question 26

electron affinity

Answer 26

- energy dissipated by a gaseous species when it gains an electron - the higher the Zeff between a nucleus and its electrons, the greater the energy release when it gains an electron - electron affinity increases across a period from left to right - electron affinity decreases from top to bottom in a group

Question 27

exothermic reaction

Answer 27

expels energy in the form of heat

Question 28

electronegativity

Answer 28

- measure of the attractive force that an atom will exert on an electron in a chemical shell - higher electronegativity means more attraction to electrons in a bond - increases from left to right and decreases from top to bottom

Question 29

alkali metals (Group 1A)

Answer 29

- have only one loosely bound valence electron - Zeff values very low, radius very high - low electronegativities, low IE, low E- - readily act with nonmetals or form univalent cations - active metal

Question 30

alkaline earth metals (Group IIA)

Answer 30

- have only two loosely bound valence electrons - Zeff values very low, radius very high - low electronegativities, low IE, low E- - readily act with nonmetals or form divalent cations - active metal

Question 31

chalcogens (Group VIA, Group 16)

Answer 31

- include both nonmetals and metalloids - not as reactive as halogens, but crucial for normal biological functions - 6 valence electrons - small atomic radii, large ionic radii - in high concentrations, all can be toxic to humans

Question 32

halogens (Group VIIA, Group 17)

Answer 32

- highly reactive nonmetals - seven valence electrons - very high E- and electron affinity - especially reactive towards alkali and alkaline earth metals - not naturally found in neutral sate but rather as halides because they are so reactive

Question 33

noble gases (Group VIIIA, Group 18) aka inert gases

Answer 33

- minimal reactivity due to their filled valence shells - high ionization energies, little to no tendency to gain or lose electrons and no measurable electronegativities - low boiling points, exist as gases at RT

Question 34

transition metals (Groups IB to VIIIB, Groups 3-12)

Answer 34

- considered to be metals, have low electron affinities, low ionization energies and low E- - high melting and boiling points, very hard, malleable, good conductors - have different possible oxidation states - tend to either associate with water molecules or nonmetals

Question 35

subtraction frequencies

Answer 35

frequencies of colors that are not absorbed; we observe the complementary color of the frequency that was observed