CHEM 121 FINAL EXAM | UPDATED QUESTIONS AND
ANSWERS UPDATED .Buy Quality Materials!
Electronegativity
A measure of the ability of an atom in a chemical compound to attract electrons (chi
symbol)
Pauling Scale of Electronegativity
O>N>C=H
salts
Ionic compounds that can be formed by replacing one or more of the hydrogen ions of
an acid with another positive ion
homonuclear diatomic molecules
diatomic molecules containing atoms of the same elements
heteronuclear diatomic molecules
molecules composed of two different nuclei
pure covalent bond
neutral atoms held together by equally shared electrons
electrostatic force
The force between electrically charged objects (like charges repel and opposite charges
attract each other).
Chemically reasonable resonance structure
where the magnitude of the formal charges are small. They represent bonding that is
typical of various elemennts.
hypervalent species
a species with a central atom with more electrons in its valence shell than predicted by
the octet rule. The oc
Why will the best structure have mimimum formal charge if two or more lewis
structures are possible?
the creation of formal charge requires a redistribution of electrons from their atomic
states
why will the best structure have the negative formal charge on the most
electronegative atom and the positive formal charge on the least electronegative
atom.
since more electronegative elements have a greater ability to attract electrons within a
covalent bond, they also have a greater ability to attract additional electrons and take on
a negative formal charge. The opposite is true for less electronegative elements.
oxidation state
the condition of an atom expressed by the number of electrons that the atom needs to
reach its elemental form
coulombic repulsion
The electrostatic force of repulsion exerted by one charged particle on another charged
particle of the same sign
Valence Shell Electron Pair Repulsion (VSEPR) Theory
as a consequence of repulsion. between valence electron pairs, all pairs are oriented as
far away as possible from each other in three dimensional space
, polar
Molecule with partial charges. Mixes with water.
Non-polar
a molecule in which all atoms have the same electronegativity and the electron
distribution is equal
free radical
an atom or a group of atoms that has one unpaired electron
functional group
A specific configuration of atoms commonly attached to the carbon skeletons of organic
molecules and involved in chemical reactions.
which two observations could 19th century physicists not explain?
1. The observation that atoms, when inserted in flames, emit light of a certain colour.
2, The observation that heated objects emit light of particular colours which change with
temperature.
quantum mechanics
Study of physics at the atomic level where energy is quantized in discrete, rather than
continuous, levels.
probability distribution
list of possible outcomes with associated probabilities
Classical description of nature
quantal descriptionn of nature
zero point energy
The lowest energy state of molecular vibration.
interference pattern
A pattern formed by the overlapping of two or more waves that arrive in a region at the
same time.
Diffraction
Occurs when an object causes a wave to change direction and bend around it
Momentum
The product of an object's mass and velocity
de Broglie Hypothesis
matter particles have a wave-like nature characterised by the de Broglie wavelength
Plank's constant
a number used to calculate the radiant energy (E) absorbed or emitted by a body based
on the frequency of radiation
standing waves
A pattern of vibration that simulates a wave standing still
sine wave
a wave whose source vibrates with simple harmonic motion (electromagnetic radiation +
debroglie waves)
axial region
y plane
equitorial region
lie on the equator of the molecule
energy. and intensity of a wave
proportional to the square of its amplitude
ANSWERS UPDATED .Buy Quality Materials!
Electronegativity
A measure of the ability of an atom in a chemical compound to attract electrons (chi
symbol)
Pauling Scale of Electronegativity
O>N>C=H
salts
Ionic compounds that can be formed by replacing one or more of the hydrogen ions of
an acid with another positive ion
homonuclear diatomic molecules
diatomic molecules containing atoms of the same elements
heteronuclear diatomic molecules
molecules composed of two different nuclei
pure covalent bond
neutral atoms held together by equally shared electrons
electrostatic force
The force between electrically charged objects (like charges repel and opposite charges
attract each other).
Chemically reasonable resonance structure
where the magnitude of the formal charges are small. They represent bonding that is
typical of various elemennts.
hypervalent species
a species with a central atom with more electrons in its valence shell than predicted by
the octet rule. The oc
Why will the best structure have mimimum formal charge if two or more lewis
structures are possible?
the creation of formal charge requires a redistribution of electrons from their atomic
states
why will the best structure have the negative formal charge on the most
electronegative atom and the positive formal charge on the least electronegative
atom.
since more electronegative elements have a greater ability to attract electrons within a
covalent bond, they also have a greater ability to attract additional electrons and take on
a negative formal charge. The opposite is true for less electronegative elements.
oxidation state
the condition of an atom expressed by the number of electrons that the atom needs to
reach its elemental form
coulombic repulsion
The electrostatic force of repulsion exerted by one charged particle on another charged
particle of the same sign
Valence Shell Electron Pair Repulsion (VSEPR) Theory
as a consequence of repulsion. between valence electron pairs, all pairs are oriented as
far away as possible from each other in three dimensional space
, polar
Molecule with partial charges. Mixes with water.
Non-polar
a molecule in which all atoms have the same electronegativity and the electron
distribution is equal
free radical
an atom or a group of atoms that has one unpaired electron
functional group
A specific configuration of atoms commonly attached to the carbon skeletons of organic
molecules and involved in chemical reactions.
which two observations could 19th century physicists not explain?
1. The observation that atoms, when inserted in flames, emit light of a certain colour.
2, The observation that heated objects emit light of particular colours which change with
temperature.
quantum mechanics
Study of physics at the atomic level where energy is quantized in discrete, rather than
continuous, levels.
probability distribution
list of possible outcomes with associated probabilities
Classical description of nature
quantal descriptionn of nature
zero point energy
The lowest energy state of molecular vibration.
interference pattern
A pattern formed by the overlapping of two or more waves that arrive in a region at the
same time.
Diffraction
Occurs when an object causes a wave to change direction and bend around it
Momentum
The product of an object's mass and velocity
de Broglie Hypothesis
matter particles have a wave-like nature characterised by the de Broglie wavelength
Plank's constant
a number used to calculate the radiant energy (E) absorbed or emitted by a body based
on the frequency of radiation
standing waves
A pattern of vibration that simulates a wave standing still
sine wave
a wave whose source vibrates with simple harmonic motion (electromagnetic radiation +
debroglie waves)
axial region
y plane
equitorial region
lie on the equator of the molecule
energy. and intensity of a wave
proportional to the square of its amplitude
