Inorganic Chemistry ACS: Study Guide
2025/2026 Exam Questions and Verified
Answers | Already Graded A+
Ionization energy - 🧠ANSWER ✔✔energy required to remove the least
tightly bound electron from a neutral atom in the gas phase
periodic trend of ionization energy - 🧠ANSWER ✔✔highest at top right-
smaller electron=harder to remove
Why is a half filled subshell so stable? - 🧠ANSWER ✔✔it serves to
maximize the stabilizing interactions while minimizing the destabilizing
interactions among electrons
exchange interaction - 🧠ANSWER ✔✔pie, stabilizing, result of electrons
pairing in degenerate orbitals with parallel spin
,pairing energy - 🧠ANSWER ✔✔destabilizing, coulomb interaction, pic,
energy of electron-electron repulsion in a filled orbital
Is it easier to ionize a high energy or low energy electrons - 🧠ANSWER
✔✔high energy electron-already contains more energy so it requires less
energy input
What happens when a 3d series metal is ionized? - 🧠ANSWER ✔✔the first
electron to be ionized will come from the 4s orbital, the other s electron will
enter the d orbital (4s03dn+1)
lanthanide contraction - 🧠ANSWER ✔✔reduction in atomic radius following
the lanthanide series, contrary to the overall trend observed for the periodic
table
lanthanides - 🧠ANSWER ✔✔elements 57-71, first appearance of f orbitals, f
orbitals are poor at shielding so any electrons dded will have a higher Zeff,
shrinking the radius
Slater's rules - 🧠ANSWER ✔✔tell us what the effective nuclear charge will
be, Zeff=Z-sigma, Z is the atomic number, sigma=sum of the number of
electrons in a given subtle multiplied by a weighting coefficient (page 1)
,Shielding - 🧠ANSWER ✔✔the reduction in charge attraction between the
nucleus and electrons due to electrons between the nucleus and the
electron in question, it is considered the be between if it has a lower energy
penetration - 🧠ANSWER ✔✔when an electron of a higher atomic orbital is
found within the shell of electrons of a lower atomic number, that is to say
that an electron of higher energy is found within an orbital of lower energy
electron affinity - 🧠ANSWER ✔✔the difference in energy for a neutral
gaseous atom, and the gaseous anion. used interchangeably with electron
gain enthalpy. more positive=more stable EA with the additional electron,
more positive EGE=more stable with extra electron
Combination of electron affinity and ionization energy - 🧠ANSWER
✔✔electronegativity, overall measure of an atoms ability to attract electrons
to itself when part of a compound, fluorine has highest electronegativity
polarizability - 🧠ANSWER ✔✔an atoms ability to be distorted by an electric
field, regions of a molecule can take on partial positive or partial negative
charge
3
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
, Why do we use the hydrogen system approximation - 🧠ANSWER
✔✔systems involving multiple electrons are much more complex, and they
require the use of quantum mechanics
What is the formula for the energy of a hydrogen orbital - 🧠ANSWER
✔✔E=-13.6(eV)*(Z^2/n^2), h is plancks constant (background on pg 4)
Energy can be expressed in... - 🧠ANSWER ✔✔Joules, wavenumber,
inverse centimeters
quantum number N - 🧠ANSWER ✔✔principle quantum number, defines
energy and size of orbital
quantum number L - 🧠ANSWER ✔✔orbital angular momentum quantum
number, defines the magnitude of the orbital angular momentum, as well as
the angular shape of the orbital, L can have values of 0 to n-1.
quantum number Ml - 🧠ANSWER ✔✔magnetic quantum number, describes
the orientation of the angular momentum, ml can have values of 0 to +/-1
quantum number Ms - 🧠ANSWER ✔✔spin magnetic quantum number,
defines intrinsic angular momentum of an electron, Ms can have values of
either +1/2 or -1/2
2025/2026 Exam Questions and Verified
Answers | Already Graded A+
Ionization energy - 🧠ANSWER ✔✔energy required to remove the least
tightly bound electron from a neutral atom in the gas phase
periodic trend of ionization energy - 🧠ANSWER ✔✔highest at top right-
smaller electron=harder to remove
Why is a half filled subshell so stable? - 🧠ANSWER ✔✔it serves to
maximize the stabilizing interactions while minimizing the destabilizing
interactions among electrons
exchange interaction - 🧠ANSWER ✔✔pie, stabilizing, result of electrons
pairing in degenerate orbitals with parallel spin
,pairing energy - 🧠ANSWER ✔✔destabilizing, coulomb interaction, pic,
energy of electron-electron repulsion in a filled orbital
Is it easier to ionize a high energy or low energy electrons - 🧠ANSWER
✔✔high energy electron-already contains more energy so it requires less
energy input
What happens when a 3d series metal is ionized? - 🧠ANSWER ✔✔the first
electron to be ionized will come from the 4s orbital, the other s electron will
enter the d orbital (4s03dn+1)
lanthanide contraction - 🧠ANSWER ✔✔reduction in atomic radius following
the lanthanide series, contrary to the overall trend observed for the periodic
table
lanthanides - 🧠ANSWER ✔✔elements 57-71, first appearance of f orbitals, f
orbitals are poor at shielding so any electrons dded will have a higher Zeff,
shrinking the radius
Slater's rules - 🧠ANSWER ✔✔tell us what the effective nuclear charge will
be, Zeff=Z-sigma, Z is the atomic number, sigma=sum of the number of
electrons in a given subtle multiplied by a weighting coefficient (page 1)
,Shielding - 🧠ANSWER ✔✔the reduction in charge attraction between the
nucleus and electrons due to electrons between the nucleus and the
electron in question, it is considered the be between if it has a lower energy
penetration - 🧠ANSWER ✔✔when an electron of a higher atomic orbital is
found within the shell of electrons of a lower atomic number, that is to say
that an electron of higher energy is found within an orbital of lower energy
electron affinity - 🧠ANSWER ✔✔the difference in energy for a neutral
gaseous atom, and the gaseous anion. used interchangeably with electron
gain enthalpy. more positive=more stable EA with the additional electron,
more positive EGE=more stable with extra electron
Combination of electron affinity and ionization energy - 🧠ANSWER
✔✔electronegativity, overall measure of an atoms ability to attract electrons
to itself when part of a compound, fluorine has highest electronegativity
polarizability - 🧠ANSWER ✔✔an atoms ability to be distorted by an electric
field, regions of a molecule can take on partial positive or partial negative
charge
3
COPYRIGHT©JOSHCLAY 2025/2026. YEAR PUBLISHED 2025. COMPANY REGISTRATION NUMBER: 619652435. TERMS OF USE. PRIVACY
STATEMENT. ALL RIGHTS RESERVED
, Why do we use the hydrogen system approximation - 🧠ANSWER
✔✔systems involving multiple electrons are much more complex, and they
require the use of quantum mechanics
What is the formula for the energy of a hydrogen orbital - 🧠ANSWER
✔✔E=-13.6(eV)*(Z^2/n^2), h is plancks constant (background on pg 4)
Energy can be expressed in... - 🧠ANSWER ✔✔Joules, wavenumber,
inverse centimeters
quantum number N - 🧠ANSWER ✔✔principle quantum number, defines
energy and size of orbital
quantum number L - 🧠ANSWER ✔✔orbital angular momentum quantum
number, defines the magnitude of the orbital angular momentum, as well as
the angular shape of the orbital, L can have values of 0 to n-1.
quantum number Ml - 🧠ANSWER ✔✔magnetic quantum number, describes
the orientation of the angular momentum, ml can have values of 0 to +/-1
quantum number Ms - 🧠ANSWER ✔✔spin magnetic quantum number,
defines intrinsic angular momentum of an electron, Ms can have values of
either +1/2 or -1/2
