CEM 141 MSU EXAM 3 COMPREHENSIVE
STUDY GUIDE 2026 CHEMICAL REACTIONS
AND STOICHIOMETRY SOLUTIONS
VERIFIED A+
◉ what's the symbol for bonding molecular orbital?
Answer: sigma
◉ what's the symbol for anti-bonding molecular orbital?
Answer: sigma*
◉ how do e- in a bonding molecular orbital interact?
Answer: e-s interact constructively/in phase
◉ how do e- in an anti-bonding molecular orbital interact?
Answer: e-s interact deconstructively/out of phase
◉ how much energy do bonding molecular orbitals have?
Answer: lower energy than atomic orbitals
,◉ how much energy do anti-bonding molecular orbitals have?
Answer: higher energy than atomic orbitals
◉ are bonding molecular orbitals stabilizing or destabilizing?
Answer: stabilizing
◉ are anti-bonding molecular orbitals stabilizing or destabilizing?
Answer: destabilizing
◉ are bonding molecular orbitals 1st or 2nd?
Answer: 1st
◉ are anti-bonding molecular orbitals 1st or 2nd?
Answer: 2nd
◉ if you combine 2 atoms with 10 atomic orbitals each, how many
molecular orbitals will results?
Answer: 20
◉ if there's unpaired electrons in a molecular orbital theory
diagram, what happens to the substance magnetic-wise?
Answer: it's magnetic - paramagnetic
, ◉ if there's only paired electrons in a molecular orbital theory
diagram, what happens to the substance magnetic-wise?
Answer: it's not magnetic - dimagnetic
◉ why are metals shiny? explain using molecular orbitals and the
energy graph
Answer: the absorption of a photon will cause an electron to go up to
a higher energy level. but it immediately falls back down, and the
photon is emitted. thus the shiny
◉ what is a molecular orbital?
Answer: lots of atomic orbitals combined w each other to form MOs
◉ why are metals conductive and malleable?
Answer: metallic bonds have uniform core e-s, but the valence e-s
are delocalized. this means they don't belong to a particular atom,
they belong to the metal itself. it's a sea of e-s. this explains
conductivity and malleability bc the electrons are able to move
◉ band theory for metals
Answer: the band overlaps
◉ band theory for semiconductive (metalloids)
STUDY GUIDE 2026 CHEMICAL REACTIONS
AND STOICHIOMETRY SOLUTIONS
VERIFIED A+
◉ what's the symbol for bonding molecular orbital?
Answer: sigma
◉ what's the symbol for anti-bonding molecular orbital?
Answer: sigma*
◉ how do e- in a bonding molecular orbital interact?
Answer: e-s interact constructively/in phase
◉ how do e- in an anti-bonding molecular orbital interact?
Answer: e-s interact deconstructively/out of phase
◉ how much energy do bonding molecular orbitals have?
Answer: lower energy than atomic orbitals
,◉ how much energy do anti-bonding molecular orbitals have?
Answer: higher energy than atomic orbitals
◉ are bonding molecular orbitals stabilizing or destabilizing?
Answer: stabilizing
◉ are anti-bonding molecular orbitals stabilizing or destabilizing?
Answer: destabilizing
◉ are bonding molecular orbitals 1st or 2nd?
Answer: 1st
◉ are anti-bonding molecular orbitals 1st or 2nd?
Answer: 2nd
◉ if you combine 2 atoms with 10 atomic orbitals each, how many
molecular orbitals will results?
Answer: 20
◉ if there's unpaired electrons in a molecular orbital theory
diagram, what happens to the substance magnetic-wise?
Answer: it's magnetic - paramagnetic
, ◉ if there's only paired electrons in a molecular orbital theory
diagram, what happens to the substance magnetic-wise?
Answer: it's not magnetic - dimagnetic
◉ why are metals shiny? explain using molecular orbitals and the
energy graph
Answer: the absorption of a photon will cause an electron to go up to
a higher energy level. but it immediately falls back down, and the
photon is emitted. thus the shiny
◉ what is a molecular orbital?
Answer: lots of atomic orbitals combined w each other to form MOs
◉ why are metals conductive and malleable?
Answer: metallic bonds have uniform core e-s, but the valence e-s
are delocalized. this means they don't belong to a particular atom,
they belong to the metal itself. it's a sea of e-s. this explains
conductivity and malleability bc the electrons are able to move
◉ band theory for metals
Answer: the band overlaps
◉ band theory for semiconductive (metalloids)
