1. Ionization energy ANS >>> It is the energy required to remove the least
tightly bound electron from a neutral atom in the gas phase.
2. What is the periodic trend in ionization energy? ANS >>> Ionization energy
is lowest at the bottom left corner of the table, and increases going up and to the
right, with the highest ionization energy being for Helium.
The trend is the same in regards to effective nuclear charge and atomic radii. In ther
words, the smaller atomic radius, the greater ionization energy and effective nuclear
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, charge.
3. What is the real reason that a half-filled subshell is so stable? ANS >>> A
half-filled subshell serves to maximize the stabilizing interactions, while minimizing
the desta- bilizing interactions among electrons.
4. What is the exchange interaction?
Is it stabilizing or destabilizing? ANS >>> The exchange interaction, e À, is the
stabilizing interaction, and it is a result of electrons pairing in degenerate orbitals
with parallel spin.
5. What is harder to ionize, a high energy electron or a low energy electron?
ANS >>> A high energy electron is easier to ionize. It already contains more energy,
so the input to remove it from the atom is less.
6. If a 3d series metal is ionized, what orbital loses the electron? What happens
to the valence configuration? ANS >>> If a d series metal has the configuration
4s^2 3d^n, the first electron to be ionized will come from the 4s orbital.
The remaining s orbital will then enter a d orbital, giving the configuration of the +1
cation 4s^0, 3d^(n+1).
7. Describe Slater's Rules ANS >>> Slater's Rules tell us what the effective nuclear
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, charge will be.
Formally, it is written as Zeff= Z - Ã.
Z is the atomic number, and Ã=s£i)(
(Si) is the number of electrons in a given subshell multiplied by a weighting coeffi-
cient.
The weighting coefficients are ANS >>>
1) A. For s and p valence electrons,
(n-2) groups or lower contribute 1.00 to si (weighting coefficient of 100%). 1.00xne
B. (n-1) groups contribute 0.85 to si. 0.85xne
C. N(s,p) groups (the valence groups) contribute 0.35 to si. 0.35xne
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, 2) For d and f valence electrons ANS >>>
A. electrons in the valence shell contribute 0.35 to si. 0.35xne
B. electrons in any lower group contribute 1.00 to si.1.00xne
8. What is shielding? ANS >>> When electrons in inner shells weaken the
attraction be- tween electrons in the outer shell
9. What is the Lanthanide Contraction? ANS >>> It is the reduction in atomic
radius following the lanthanide series, contrary to the overall trend observed for the
periodic table. The lanthanides are elements 57 through 71, and are the first
appearance of filled f orbitals.
F orbitals are poor at shielding, so any electrons added into the subshell following
the f orbital experience a higher effective nuclear charge, shrinking their radius over
what is to be expected from overall trends.
10. What is penetration? ANS >>> Describes when an electron of a higher atomic
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tightly bound electron from a neutral atom in the gas phase.
2. What is the periodic trend in ionization energy? ANS >>> Ionization energy
is lowest at the bottom left corner of the table, and increases going up and to the
right, with the highest ionization energy being for Helium.
The trend is the same in regards to effective nuclear charge and atomic radii. In ther
words, the smaller atomic radius, the greater ionization energy and effective nuclear
mailto:https://www.stuvia.com/en-us/user/techgrades
, charge.
3. What is the real reason that a half-filled subshell is so stable? ANS >>> A
half-filled subshell serves to maximize the stabilizing interactions, while minimizing
the desta- bilizing interactions among electrons.
4. What is the exchange interaction?
Is it stabilizing or destabilizing? ANS >>> The exchange interaction, e À, is the
stabilizing interaction, and it is a result of electrons pairing in degenerate orbitals
with parallel spin.
5. What is harder to ionize, a high energy electron or a low energy electron?
ANS >>> A high energy electron is easier to ionize. It already contains more energy,
so the input to remove it from the atom is less.
6. If a 3d series metal is ionized, what orbital loses the electron? What happens
to the valence configuration? ANS >>> If a d series metal has the configuration
4s^2 3d^n, the first electron to be ionized will come from the 4s orbital.
The remaining s orbital will then enter a d orbital, giving the configuration of the +1
cation 4s^0, 3d^(n+1).
7. Describe Slater's Rules ANS >>> Slater's Rules tell us what the effective nuclear
mailto:https://www.stuvia.com/en-us/user/techgrades
, charge will be.
Formally, it is written as Zeff= Z - Ã.
Z is the atomic number, and Ã=s£i)(
(Si) is the number of electrons in a given subshell multiplied by a weighting coeffi-
cient.
The weighting coefficients are ANS >>>
1) A. For s and p valence electrons,
(n-2) groups or lower contribute 1.00 to si (weighting coefficient of 100%). 1.00xne
B. (n-1) groups contribute 0.85 to si. 0.85xne
C. N(s,p) groups (the valence groups) contribute 0.35 to si. 0.35xne
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, 2) For d and f valence electrons ANS >>>
A. electrons in the valence shell contribute 0.35 to si. 0.35xne
B. electrons in any lower group contribute 1.00 to si.1.00xne
8. What is shielding? ANS >>> When electrons in inner shells weaken the
attraction be- tween electrons in the outer shell
9. What is the Lanthanide Contraction? ANS >>> It is the reduction in atomic
radius following the lanthanide series, contrary to the overall trend observed for the
periodic table. The lanthanides are elements 57 through 71, and are the first
appearance of filled f orbitals.
F orbitals are poor at shielding, so any electrons added into the subshell following
the f orbital experience a higher effective nuclear charge, shrinking their radius over
what is to be expected from overall trends.
10. What is penetration? ANS >>> Describes when an electron of a higher atomic
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