Chapter 2

Question 1

Modern periodic table arranges elements into …

Answer 1

periods (rows) and groups/families (columns) based on atomic number

Question 2

A Elements (Representative Elements)

Answer 2

Groups IA through VIIIA
* Valence electrons in orbitals of s or p subshells

Question 3

B Elements (Nonrepresentative Elements)

Answer 3

Transition elements, lanthanides, actinides

Question 4

Metals

Answer 4

• Left side and middle of PT
• Active metals, transition metals, lanthanides, actinides
• Lustruous (shiny) EXCEPT for mercury
• High melting points and densities EXCEPT for lithium
• Deform without breaking
• Malleable (hammered in to shapes
• Ductility (can be pulled or drawn in to wires
• Low electronegativity, high electropositivity
• Large AR
• Small IR
• Good conductors

Question 5

Nonmetals

Answer 5

• Upper right of PT
• Brittle
• No luster
• High ionization energy and electronjegativity
• Small AR
• Large IR
• Poor conductors
• Negative oxidation states

Question 6

Metalloids/Semimetals

Answer 6

• Characteristics of metals and nonmetals
• Form staircase on PT
• B, Si, Ge, As, Sb, Te, Po, At

Question 7

Effective Nuclear Charge (Zeff)

Answer 7

Electrostatic attraction between valence shell electrons and nucleus
* Net + charge experienced by outermost electrons
* Increases left to right and up

Question 8

Principal Quantum Number Trend

Answer 8

Increases as moves down PT

Question 9

Atomic Radius

Answer 9

1/2 the distance between centers of two atoms of an element that are briefly in contact
* Increases right to left and down

Question 10

Ionic Radii

Answer 10

Question 11

Ionization Energy (IE)/Ionization Potential

Answer 11

Energy required to remove an electron from a gaseous species
* Endothermic process (requires heat)
* Increases left to right and up across periodic table

Question 12

First Ionization Energy

Answer 12

Energy needed to remove the first electron

Question 13

Second Ionization Energy

Answer 13

Energy necessary to remove second electron from univalent cation (X+) to form divalent cation (X2+)
* Higher than first ionization energy

Question 14

Electron Affinity

Answer 14

Energy dissipated by gas when it gains an electron
* Exothermic (expels heat)

Question 15

Electronegativity

Answer 15

Measure of attractive force an atom will exert on an electron in a chemical bond
* Greater electronegativity, the more it attracts electrons
* Follows same pattern as ionization energy

Question 16

Periodic table trends

Answer 16

Question 17

Alkali Metals

Answer 17

• Group 1
• Lower density for metals
• Largest AR
• Easily lose an electron to form cations
• React easily with nonmetals ESPECIALLY halogens

Question 18

Alkaline Earth Metals

Answer 18

• Group 2
• Slighlty higher Zeff and smaller AR
• Two electrons easily removed to form divalent cations
• Aren’t naturally found in neutral state
• Highly reactive to water

Question 19

Chalcogens

Answer 19

• Group 16
• Nonmetals and metalloids
• Small AR and large IR
• At high concentrations are toxic/damaging

Question 20

Halogens

Answer 20

• Group 17
• Highly reactive nonmetals
• Desperate to complete octet by gaining an electron
• Especially reactive to Alkali and Alkaline Earth Metals
• Found as ions (halides) or diatomic molecules

Question 21

Noble Gases

Answer 21

• Group 18
• Inert gases because minimal reactivity since filled valence shells
• High ionization energy
• No electronegativity

Question 22

Transition Metals

Answer 22

• Groups 3 - 12
• Metal
• Low electron affinities, low ionization energies, and low electronegativities
• High melting MP & BP
• Have different possible charged forms (oxidation states)
• Valence electrons increases as atomic number increases