INORGANIC CHEMISTRY ACS EXAM
Practice Questions and Answers 2026 |
Updated Revision Pack | Grade A+
• Ionization energy. CORRECT ANSWER: energy required to remove the
least tightly bound electron from a neutral atom in the gas phase
• periodic trend of ionization energy. CORRECT ANSWER: highest at top
right-smaller electron=harder to remove
• Why is a half filled subshell so stable?. CORRECT ANSWER: it serves to
maximize the stabilizing interactions while minimizing the destabilizing
interactions among electrons
• exchange interaction. CORRECT ANSWER: pie, stabilizing, result of
electrons pairing in degenerate orbitals with parallel spin
• pairing energy. CORRECT 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. CORRECT
ANSWER: high energy electron-already contains more energy so it
requires less energy input
,• What happens when a 3d series metal is ionized?. CORRECT 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. CORRECT ANSWER: reduction in atomic radius
following the lanthanide series, contrary to the overall trend observed
for the periodic table
• lanthanides. CORRECT 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. CORRECT 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. CORRECT 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. CORRECT 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. CORRECT 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. CORRECT
ANSWER: electronegativity, overall measure of an atoms ability to
attract electrons to itself when part of a compound, fluorine has
highest electronegativity
• polarizability. CORRECT ANSWER: an atoms ability to be distorted by
an electric field, regions of a molecule can take on partial positive or
partial negative charge
• Why do we use the hydrogen system approximation. CORRECT
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. CORRECT
ANSWER: E=-13.6(eV)*(Z^2/n^2), h is plancks constant (background on
pg 4)
• Energy can be expressed in.... CORRECT ANSWER: Joules,
wavenumber, inverse centimeters
, • quantum number N. CORRECT ANSWER: principle quantum number,
defines energy and size of orbital
• quantum number L. CORRECT 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. CORRECT ANSWER: magnetic quantum number,
describes the orientation of the angular momentum, ml can have
values of 0 to +/-1
• quantum number Ms. CORRECT ANSWER: spin magnetic quantum
number, defines intrinsic angular momentum of an electron, Ms can
have values of either +1/2 or -1/2
• Radial wavefunction. CORRECT ANSWER: (R(r)), along with the
angular wavefunction, gives us the orbitals. With a wave function it is
possible to completely characterize a particle, goes to zero at infinity,
produce characteristic shapes when graphed
• Radial distribution function. CORRECT ANSWER: a plot of R^2(r)r^2,
tells us probability of finding an electron at a certain distance from the
nucleus, every orbital has a different radial distribution function and a
node on the graph is a region of zero probability
Practice Questions and Answers 2026 |
Updated Revision Pack | Grade A+
• Ionization energy. CORRECT ANSWER: energy required to remove the
least tightly bound electron from a neutral atom in the gas phase
• periodic trend of ionization energy. CORRECT ANSWER: highest at top
right-smaller electron=harder to remove
• Why is a half filled subshell so stable?. CORRECT ANSWER: it serves to
maximize the stabilizing interactions while minimizing the destabilizing
interactions among electrons
• exchange interaction. CORRECT ANSWER: pie, stabilizing, result of
electrons pairing in degenerate orbitals with parallel spin
• pairing energy. CORRECT 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. CORRECT
ANSWER: high energy electron-already contains more energy so it
requires less energy input
,• What happens when a 3d series metal is ionized?. CORRECT 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. CORRECT ANSWER: reduction in atomic radius
following the lanthanide series, contrary to the overall trend observed
for the periodic table
• lanthanides. CORRECT 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. CORRECT 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. CORRECT 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. CORRECT 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. CORRECT 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. CORRECT
ANSWER: electronegativity, overall measure of an atoms ability to
attract electrons to itself when part of a compound, fluorine has
highest electronegativity
• polarizability. CORRECT ANSWER: an atoms ability to be distorted by
an electric field, regions of a molecule can take on partial positive or
partial negative charge
• Why do we use the hydrogen system approximation. CORRECT
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. CORRECT
ANSWER: E=-13.6(eV)*(Z^2/n^2), h is plancks constant (background on
pg 4)
• Energy can be expressed in.... CORRECT ANSWER: Joules,
wavenumber, inverse centimeters
, • quantum number N. CORRECT ANSWER: principle quantum number,
defines energy and size of orbital
• quantum number L. CORRECT 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. CORRECT ANSWER: magnetic quantum number,
describes the orientation of the angular momentum, ml can have
values of 0 to +/-1
• quantum number Ms. CORRECT ANSWER: spin magnetic quantum
number, defines intrinsic angular momentum of an electron, Ms can
have values of either +1/2 or -1/2
• Radial wavefunction. CORRECT ANSWER: (R(r)), along with the
angular wavefunction, gives us the orbitals. With a wave function it is
possible to completely characterize a particle, goes to zero at infinity,
produce characteristic shapes when graphed
• Radial distribution function. CORRECT ANSWER: a plot of R^2(r)r^2,
tells us probability of finding an electron at a certain distance from the
nucleus, every orbital has a different radial distribution function and a
node on the graph is a region of zero probability
