Ch. 2: The Periodic Table

Question 1

Periodic Table of Elements

Answer 1

Organizes the elements according to their atomic numbers and reveals a pattern of similar chemical and physical properties among elements

Question 2

Periods

Answer 2

Rows, based on the same principal energy level, n

Question 3

Groups/families

Answer 3

Columns, electrons in the same group have the same valence shell electron configuration

Question 4

Representative Elements

Answer 4

“A elements” (IA through VIIIA have their valence electrons in the orbitals of either s or p subshells

Question 5

Nonrepresentative Elements

Answer 5

“B elements” include transition elements which have valence electrons in the s and d subshells and the lanthanide and actinide series which have valence electrons in the s and f subshells

Question 6

Metals

Answer 6

Shiny (lustrous), conduct electricity well, and are malleable and ductile. They are found on the left side and middle of the periodic table

Question 7

Nonmetals

Answer 7

Dull, poor conductors of electricty and are brittle. Found on the right side of the periodic table

Question 8

Metalloids

Answer 8

Possess characteristics of both metals and nonmetals and are found in a stair-step pattern starting with boron (B)

Question 9

Effective Nuclear Charge (Zeff)

Answer 9

Net positive charge experienced by the elecrons in the valence shell and forms the foundation for all periodic trends

• Zeff increases from left to right across a period, w litle change from top to bottom in a foup
• Valence electrons become increasingly separated from the nucleus as the principal energy level, n, increases from top to bottom in a group

Question 10

Atomic Radius

Answer 10

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

Question 11

Ionic Radius

Answer 11

Size of a charged species. The largest nonmetallic ionic radii and the smallest metallic ionic radii exist at the metalloid boundary.

• Cations are generally smaller than their neutral atom
• Anions are generally larger than their neutral atom

Question 12

Ionization Energy

Answer 12

Amount of energy necesary to remove an electron from the valence shell of a gaseous species; it increases from left to right across a period and decreases from top to bottom in a a group

Question 13

Electron Affinity

Answer 13

Amount of energy released when a gaseous species gains an electron in its valnence shell; it increases from left to right across a period and decreasses from top to bottom in a group

Question 14

Electronegativity

Answer 14

Measure of the attractive force of the nucleus for electrons within a bond; it increases from left to right across a period and decreases from top to bottom in a group

Question 15

Alkali Metals

Answer 15

Typically take on an oxidation state of +1 and prefer to lose an electron to achieve a noble gas-like configuration; they and the alkaline earth metals are the most reactive of all metals, possess most for the classsic physical properties of metals, except their densitities are lower than those of other metals

Question 16

Alkaline Earth Metals

Answer 16

Take on an oxidation state of +2 and can lose 2 electrons to achieve noble gas-like configurations

Question 17

Chalcogens

Answer 17

Take on oxidation states of -2 or +6 (depending on whether they are nonmetals or metals, respectively) in order to achieve noble gas configuration. They are very biologically inmportant

Question 18

Halogens

Answer 18

Typically take on an oxidation state of -1 and prefer to gain an electron to achieve noble gas-like configurations; these nonmetals have the highest electronegativities, highly reactive

Question 19

Noble Gases

Answer 19

Have a fully filled valence shell in their standard state and prefer not to give up or take on additional electrons; they have very high ionization energies and (for He, Ne, and Ar) virtually nonexistent electronegativies and electon affinities

Question 20

Transition Metals

Answer 20

Unique bc they take on multiple oxidation states, which explains their ability to form colorful complexes with nonmetals in solution and their utility in certain biological systems