Chapter 5 Notes

Question 1

One-half the distance between the nuclei of identical atoms that are bonded together

• Decrease moving left to right across the periodic table because of increasing positive charge of the nucleus
• generally increase down a group due to higher occupied energy levels

Answer 1

Atomic radius

Question 2

Largest element since atomic radii decrease moving right

Answer 2

Na

Question 3

Largest element since radii increase moving down

Answer 3

Ba

Question 4

Energy required to remove one electron from a neutral atom of am element

Answer 4

Ionization Energy

Question 5

An atom or group of bonded atoms with a positive or negative charge

Answer 5

Ion

Question 6

Process that results in formation of an ion

• increase from left to right within a period due to increased nuclear attraction for electrons. Group 18 highest group 1 lowest
• generally decreases down within groups because e- are farther from the nuclear attraction and inner electrons shield some of the nuclear charge

Answer 6

Ionization

Question 7

Energy needed to remove a second electron from an atom. IE 2 is always higher due to increased nuclear attraction after each e- is removed

Answer 7

Second Ionization Energy

Question 8

Energy change that occurs when an electron is acquired by a neutral atom

A + e- ——- A- + energy
(Energy released: - value)
Some atoms must be “forced” to gain an extra e: A + e- + energy ——- A (Energy absorbed: + value)

• increases from left to right because more energy is released when the e- is added to these atoms. Becomes more negative
• generally decreases moving down within a group due to the larger atomic radius. Less tendency to attract e-; less energy released when e- is added; lower - value
• ALWAYS MORE DIFFICULT TO ADD 2nd e- to an already - ion. 2nd is always + in value

Answer 8

Electron Affinity

Question 9

Positive ions produced when atoms lose e-
Always smaller than their atoms
Metals form ____ by losing e-
Sizes decrease from left to right & increase from top to bottom

Answer 9

Cations

Question 10

Negative ions produced when atoms gain e-
Always larger than their atoms
Nonmetals form _____ by gaining e-
Sizes decrease from left to right & increase from top to bottom

Answer 10

Anions

Question 11

Form when e- are lost gained or shared between atoms

Answer 11

Chemical compounds

Question 12

Electrons available to be lost gained or shared in the formation of chemical compounds. Usually those e- in an incompletely filled main level.

Answer 12

Valence electrons

Question 13

Group configuration
ns 1

Valence electrons
1

Answer 13

Group 1

Question 14

GC ns2

VE 2

Answer 14

Group # 2

Question 15

GC ns2p1

VE 3

Answer 15

Group # 13

Question 16

GC ns2 p2

VE 4

Answer 16

Group 14

Question 17

GC ns2 p3

VE 5

Answer 17

Group 15

Question 18

GC ns2 p4

VE 6

Answer 18

Group 16

Question 19

GC ns2 p5

VE 7

Answer 19

Group 17

Question 20

GC ns2 p6

VE 8

Answer 20

Group 18

Question 21

Measure of the ability of an atom in a chemical compound to attract electrons
Flourine - highest value (4.0)
Increases from left to right
Generally decreases down in a group
F O N and halogens have the highest values

Answer 21

Electronegativity

Question 22

Atomic radii: less regular due to partially filled d sub levels
1st ionization energy generally increases down each group (less shielding effect)
Electrons are lost in reverse order from e configuration
Most d-block elements form +2 ions. Some form +3 or +1
Low electronegativity values

Answer 22

Periodic properties of d- and f- block elements