Chapter 8: Atomic Electron Configuration and Chemical Periodicity
Chapter 8 Problem Set
Pages 366-371
11, 17, 19, 23, 33, 38, 42, 47, 51, 54, 67, Summary Question 92
8.1 ELECTRON SPIN
The fourth quantum number is …
Paramagnetism and Unpaired Electrons
A material that is slightly repelled by a strong magnet is said to be…
Materials that are attracted to a weak magnet are…
What evidence supports the concept that the electron spin is quantizied?
How can we account for the fact that the H atom is paramagnetic and the He atom is diamagnetic?
8.2 THE PAULI EXCLUSION PRINCIPLE
A statement of the Pauli exclusion principle is that no two electrons in an atom can have the same set
of…
A consequence of the exclusion principle is that no atomic orbital can contain more than…
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The four quantum numbers for the two electrons in the H atom are…
The four quantum numbers for the two electrons in the He atom are…
8.3 ATOMIC SUBSHELL ENERGIES AND ELECTRON ASSIGNMENTS
Experimental Evidence for Electron Configuration
What is ionization energy?
Why is the second ionization energy always greater than the first?
Why is the second ionization energy for Li, Na, and K much greater than that for the removal of the
second electron from Be, Mg, and Ca?
Why are some ratios, page 339 (2nd I.E./1st I.E.) slightly larger than those of other elements in the same
row?(omit the ratios of the relevant alkali metal)?
Order of Subshell Energies and Assignments
What is the n +  rule?
How can the periodic table be used to predict the electron configurations of atoms?
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Effective Nuclear Charge, Z *
What is the effective nuclear charge?
Why does the third electron in lithium occupy the 2s Subshell rather than the 2p Subshell?
What is the average shielded charge?
Filling order for electrons in energy levels and sublevels is found by adding n+ 
n
 =0
8
8s (8)
7
7s (7) 7p (8)
6
6s (6) 6p (7) 6d (8)
5
5s (5) 5p (6) 5d (7) 5f (8)
4
4s (4) 4p (5) 4d (6) 4f (7)
3
3s (3) 3p (4) 3d (5)
2
2s (2) 2p (3)
1
1s (1)
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 =1
 =2
 =3
3
8.4 ATOMIC ELECTRON CONFIGURATION
Electron Configuration of the Main Group Elements
What is the spectroscopic notation (electron configuration notation) for the lithium atom?
What is the orbital box diagram (box and arrow) for the boron atom?
What is Hund’s rule?
What is the orbital box diagram for the oxygen atom?
What is the spectroscopic notation for the potassium atom?
What is the noble gas notation for potassium?
Electron Configuration for the Transition Elements
Elements whose atoms are filling the d subshell are called…
The inner transition elements whose atoms are filling the 4f subshell are called…
Those filling the 5f Subshell are called…
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8.5 ELECTRON CONFIGURATIONS OF IONS
When atoms form ions, electrons are removed from the electron shell of highest n. If there is a choice
of Subshell within the nth shell, the electron or electrons of maximum  are removed. For example…
When transition metal atoms form positive ions, the outer s electrons are lost first. For example…
8.6 ATOMIC PROPERTIES AND PERIODIC TRENDS
Lothar Meyer (1830-1895) and Dmitri Mendeleev (1834-1907) created periodic tables by…
Electron configurations are related to some of the physical properties if the elements.
Atomic Size
What is the covalent radius
For the main group elements, atomic radii increase going down a group in the periodic table. Why?
For the main group elements, atomic radii decrease going across a period. 2 IMPORTANT effects
Page 354

The size of an atom…

For main group…
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The periodic trend in the atomic radii of the transition metal atoms is somewhat different the for main
group elements. Why?
Ionization Energy
Removing each subsequent electron requires more and more energy. Why?
For main group elements, first ionization energies increase across a period and decrease down a
group. Why?
Why does a dip to lower ionization energy occur on passing from Group 5A to Group 6A?
Electron Affinity
A measure of the electron affinity, EA, of an atom is the…
Electron affinity and ionization energy are similar in that they represent the energy required…
The periodic trends of EA and IE are closely related.
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Ion Sizes
The radius of a cation is always much smaller than that of the atom from which it is derived. Why?
The decrease in ion size is especially great when the last electron of a particular shell is moved.
Anions are always larger than the atoms from which they are derived. Why?
8.7 PERIODIC TRENDS AND CHEMICAL PROPERTIES
Ionization and the Formation of Ionic Compounds
Alkali metals form 1+ ions not 2+ ion. Why?
Main group metals generally form cations with an electron configuration equivalent to that of the
nearest noble gas. For example…
When reacting with metals, nonmetals generally acquire enough electrons to form an anion with the
electron configuration of the next higher noble gas.
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Atomic and Ionic Radii and Similarities Among Transition Metals
There is not an increase in the atomic radius in going from the second to the third transition series if
transition metals. Why?
What is the lanthanide contraction?
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