MSU CEM 141 FINAL EXAM QUESTIONS AND
ANSWERS VERIFIED 100% CORRECT
What does quantum number "n" mean? - ANSWER -Determines the energy of the
electron and identifies its shell.
change in matter is accompanied by a change in_______ - ANSWER -energy
What does quantum number "l" mean? - ANSWER -Identifies the type of orbital
(s,p,d) and subshell
= 0 - n-1.
change in energy caused by a change in ______ - ANSWER -forces
What does quantum number "ml" mean? - ANSWER -Specifies a particular orbital
within a subshell
= -l - +l (2l + 1 possible values)
tells us how many s,p,d orbitals are found in each sub shell.
energy units - ANSWER -joule (kg/m^2s^2) and calories.
What does quantum number "ms" mean? - ANSWER -Describes the spin of the
electron in each orbital
= +1/2 or -1/2
(only 2 e- in each orbital, each one has either + spin or - spin).
kinetic energy - ANSWER -Energy in motion
KE=1/2(mv^2)
Aufbau Principle - ANSWER -Principle that electrons occupy the lowest level
orbitals first.
, potential energy - ANSWER --energy associated with the position of a system of
objects in a field
-"stored energy"
Hund's Rule - ANSWER -Rule that electrons occupy orbitals of the same energy
singly until they have to pair up.
total energy - ANSWER -potential+kinetic
Core Electrons - ANSWER -Low in energy electrons that are close to the nucleus
within the closed shell, doesn't participate in reactions.
energy - ANSWER -can be transferred or transformed
Valence Electrons - ANSWER -High in energy electrons that are outside of closed
shell and determine reactivity.
London dispersion forces - ANSWER --caused by fluctuations of electron density
in molecule
-causes atoms to stick together and attract
-present in all neutral atoms
Atomic Radius - ANSWER -Half the distance between two nuclei, increases down
a group, decreases across a row
Depends on attraction of protons and electrons and repulsions of electrons
Represents state where forces between attraction and repulsion in an atom are
equal.
to lose energy ... - ANSWER -add atoms because the energy will transfer
Effective Nuclear Charge - ANSWER -= Protons - Core Electrons
Increases across the row, decreases down the group (as atomic radius decreases)
How tight the electrons are being attracted to the nucleus.
, why do atoms fly apart - ANSWER -when there are collisions. and there is more
kinetic energy as the temperature increases
Ions - ANSWER -Atoms in which electrons have been added/removed.
when a single chemical bond is broken energy is _____ - ANSWER -absorbed
Cations - ANSWER -Result of removing an electron, positively charged, smaller
atomic radius.
Why are some London dispersion forces larger - ANSWER -because some atoms
have more electrons so the electron cloud is easier to distort.
Anion - ANSWER -Result of adding an electron, negatively charged, larger
atomic radius.
as the London dispersion forces increase the melting/boiling point ______ -
ANSWER -increases because there is a stronger reaction
Isoelectronic Series - ANSWER -Atoms with the same number of electrons but
different number of protons, the attraction between electrons and protons increases
as the charge of the nucleus increases.
Why do atoms attract each other? - ANSWER -because of the attractive
electromagnetic forces between them
Ionization Energy - ANSWER -The energy required to remove an electron from
an atom in the gas phase
Decreases down a group (removing an electron gets easier as atom gets bigger),
increases across a row
Easier to remove a lone e- from a p orbital and the first paired e-.
attractions _____ the potential energy. repulsions _____ the potential energy -
ANSWER -lower; raise
ANSWERS VERIFIED 100% CORRECT
What does quantum number "n" mean? - ANSWER -Determines the energy of the
electron and identifies its shell.
change in matter is accompanied by a change in_______ - ANSWER -energy
What does quantum number "l" mean? - ANSWER -Identifies the type of orbital
(s,p,d) and subshell
= 0 - n-1.
change in energy caused by a change in ______ - ANSWER -forces
What does quantum number "ml" mean? - ANSWER -Specifies a particular orbital
within a subshell
= -l - +l (2l + 1 possible values)
tells us how many s,p,d orbitals are found in each sub shell.
energy units - ANSWER -joule (kg/m^2s^2) and calories.
What does quantum number "ms" mean? - ANSWER -Describes the spin of the
electron in each orbital
= +1/2 or -1/2
(only 2 e- in each orbital, each one has either + spin or - spin).
kinetic energy - ANSWER -Energy in motion
KE=1/2(mv^2)
Aufbau Principle - ANSWER -Principle that electrons occupy the lowest level
orbitals first.
, potential energy - ANSWER --energy associated with the position of a system of
objects in a field
-"stored energy"
Hund's Rule - ANSWER -Rule that electrons occupy orbitals of the same energy
singly until they have to pair up.
total energy - ANSWER -potential+kinetic
Core Electrons - ANSWER -Low in energy electrons that are close to the nucleus
within the closed shell, doesn't participate in reactions.
energy - ANSWER -can be transferred or transformed
Valence Electrons - ANSWER -High in energy electrons that are outside of closed
shell and determine reactivity.
London dispersion forces - ANSWER --caused by fluctuations of electron density
in molecule
-causes atoms to stick together and attract
-present in all neutral atoms
Atomic Radius - ANSWER -Half the distance between two nuclei, increases down
a group, decreases across a row
Depends on attraction of protons and electrons and repulsions of electrons
Represents state where forces between attraction and repulsion in an atom are
equal.
to lose energy ... - ANSWER -add atoms because the energy will transfer
Effective Nuclear Charge - ANSWER -= Protons - Core Electrons
Increases across the row, decreases down the group (as atomic radius decreases)
How tight the electrons are being attracted to the nucleus.
, why do atoms fly apart - ANSWER -when there are collisions. and there is more
kinetic energy as the temperature increases
Ions - ANSWER -Atoms in which electrons have been added/removed.
when a single chemical bond is broken energy is _____ - ANSWER -absorbed
Cations - ANSWER -Result of removing an electron, positively charged, smaller
atomic radius.
Why are some London dispersion forces larger - ANSWER -because some atoms
have more electrons so the electron cloud is easier to distort.
Anion - ANSWER -Result of adding an electron, negatively charged, larger
atomic radius.
as the London dispersion forces increase the melting/boiling point ______ -
ANSWER -increases because there is a stronger reaction
Isoelectronic Series - ANSWER -Atoms with the same number of electrons but
different number of protons, the attraction between electrons and protons increases
as the charge of the nucleus increases.
Why do atoms attract each other? - ANSWER -because of the attractive
electromagnetic forces between them
Ionization Energy - ANSWER -The energy required to remove an electron from
an atom in the gas phase
Decreases down a group (removing an electron gets easier as atom gets bigger),
increases across a row
Easier to remove a lone e- from a p orbital and the first paired e-.
attractions _____ the potential energy. repulsions _____ the potential energy -
ANSWER -lower; raise
