INORGANIC CHEMISTRY ACS STUDY GUIDE
EXAMS WITH CORRECT ANSWERS 2026/2027
Zeff increases - ANSWER-across the periodic table left to right
Ionization energy increases - ANSWER-left to right across a row and up column of the
periodic table
Electron affinity increases - ANSWER-left to right across a row and up a column of the
periodic table
Element size increases - ANSWER-right to left across and row and down a column of the
periodic table
Ionization energy - ANSWER-the energy required to remove an electron from an atom
Electron affinity - ANSWER-the energy required to add an electron to an atom
In M.O. theory, the number of atomic orbitals must equal... - ANSWER-the number of
molecular orbitals
M.O. requirements - ANSWER-1. M.O.s must be built from symmetrically appropriate
orbitals
2. Energy in bond pairs needs to be approximately the same
, 3. Efficient overlap of orbitals in a bond
Anti bonding orbitals - ANSWER-higher in energy than bonding orbitals, created by
overlap of orbitals that are out of phase with each other, contain nodes
Node - ANSWER-a region with no electron density
Bond order - ANSWER-b=0.5(# bonding electrons - # anti-bonding electrons)
tells you how many bonds to expect in a molecule
M.O.s for B2, C2, and N2 - ANSWER-there is a small change in energy between 2s and
2p orbitals, causing them to mix
this results in the 3 sigma orbital to be higher in energy than the 1 pi orbital
Heteronuclear M.O. theory - ANSWER-the more electronegative atom is lower in energy
Non-bonding orbitals - ANSWER-essentially lone pairs, caused when the overlap
between orbitals is not enough
CO M.O. diagram - ANSWER-reaction takes place at carbon because the frontier orbital
is mainly "carbon-like" in character
the 3 sigma orbital switches places with the 1 pi orbital
"X-like character" in M.O. - ANSWER-an orbital has "x-like character" when it is much
closer in energy to one atom rather than the other
EXAMS WITH CORRECT ANSWERS 2026/2027
Zeff increases - ANSWER-across the periodic table left to right
Ionization energy increases - ANSWER-left to right across a row and up column of the
periodic table
Electron affinity increases - ANSWER-left to right across a row and up a column of the
periodic table
Element size increases - ANSWER-right to left across and row and down a column of the
periodic table
Ionization energy - ANSWER-the energy required to remove an electron from an atom
Electron affinity - ANSWER-the energy required to add an electron to an atom
In M.O. theory, the number of atomic orbitals must equal... - ANSWER-the number of
molecular orbitals
M.O. requirements - ANSWER-1. M.O.s must be built from symmetrically appropriate
orbitals
2. Energy in bond pairs needs to be approximately the same
, 3. Efficient overlap of orbitals in a bond
Anti bonding orbitals - ANSWER-higher in energy than bonding orbitals, created by
overlap of orbitals that are out of phase with each other, contain nodes
Node - ANSWER-a region with no electron density
Bond order - ANSWER-b=0.5(# bonding electrons - # anti-bonding electrons)
tells you how many bonds to expect in a molecule
M.O.s for B2, C2, and N2 - ANSWER-there is a small change in energy between 2s and
2p orbitals, causing them to mix
this results in the 3 sigma orbital to be higher in energy than the 1 pi orbital
Heteronuclear M.O. theory - ANSWER-the more electronegative atom is lower in energy
Non-bonding orbitals - ANSWER-essentially lone pairs, caused when the overlap
between orbitals is not enough
CO M.O. diagram - ANSWER-reaction takes place at carbon because the frontier orbital
is mainly "carbon-like" in character
the 3 sigma orbital switches places with the 1 pi orbital
"X-like character" in M.O. - ANSWER-an orbital has "x-like character" when it is much
closer in energy to one atom rather than the other
