Suggest videos to teach the content? The following content is from the AP Chemistry Course and Exam Description for 
TOPIC 1.1
Moles and
Molar Mass
TOPIC 1.2
Mass Spectroscopy
of Elements
Pure Substances
TOPIC 1.3
Elemental
Composition of
Pure Substances
TOPIC 1.4
Composition
of Mixtures
TOPIC 1.5
Atomic Structure and
Electron Configuration
TOPIC 1.6
Photoelectron
Spectroscopy
TOPIC 1.7
Periodic Trends
TOPIC 1.8
Valence Electrons and
Ionic Compounds
Content:
Identify an appropriate
theory, definition, or
mathematical relationship
to solve a problem.
The mole allows different units to be compared. 
Calculate quantities of a
substance or its relative
number of particles using
dimensional analysis and the
mole concept.
One cannot count particles directly while
performing laboratory work. Thus, there must
be a connection between the masses of
substances reacting and the actual number of
particles undergoing chemical changes.
Avogadro’s number (N = 6.022 × 1023 mol−1
A )
provides the connection between the number
of moles in a pure sample of a substance and
the number of constituent particles (or formula
units) of that substance.
Expressing the mass of an individual atom
or molecule in atomic mass units (amu) is
useful because the average mass in amu of
one particle (atom or molecule) or formula
unit of a substance will always be numerically
equal to the molar mass of that substance
in grams. Thus, there is a quantitative
connection between the mass of a substance
and the number of particles that the
substance contains.
EQN: n = m/M
The mole allows different units to be compared. 
Explain the quantitative
relationship between the
mass spectrum of an element
and the masses of the
element’s isotopes.
The mass spectrum of a sample containing a
single element can be used to determine the
identity of the isotopes of that element and the
relative abundance of each isotope in nature.
The average atomic mass of an element can
be estimated from the weighted average of
the isotopic masses using the mass of each
isotope and its relative abundance.
Identify a testable scientific
question based on an
observation, data, or
a model.
Chemical formulas identify substances by their unique combination of atoms. 
Explain the quantitative
relationship between the
elemental composition by
mass and the empirical
formula of a pure substance.
Some pure substances are composed of
individual molecules, while others consist
of atoms or ions held together in fixed
proportions as described by a formula unit.
According to the law of definite proportions,
the ratio of the masses of the constituent
elements in any pure sample of that compound
is always the same.
The chemical formula that lists the lowest
whole number ratio of atoms of the elements in
a compound is the empirical formula.
Chemical formulas identify substances by their unique combination of atoms. 
Explain the quantitative
relationship between the
elemental composition by
mass and the composition of
substances in a mixture. 
While pure substances contain molecules or
formula units of a single type, mixtures contain
molecules or formula units of two or more
types, whose relative proportions can vary.
Elemental analysis can be used to determine
the relative numbers of atoms in a substance
and to determine its purity
Atoms and molecules can be identified by their electron distribution and energy.
Represent the electron
configuration of an element
or ions of an element using
the Aufbau principle. 
The atom is composed of negatively charged
electrons and a positively charged nucleus that
is made of protons and neutrons.
Coulomb’s law is used to calculate the force
between two charged particles.
EQN: Fcoulombic ∝ q1
q2
r
In atoms and ions, the electrons can be thought
of as being in “shells (energy levels)” and
“subshells (sublevels),” as described by the
electron configuration. Inner electrons are called
core electrons, and outer electrons are called
valence electrons. The electron configuration is
explained by quantum mechanics, as delineated
in the Aufbau principle and exemplified in the
periodic table of the elements.
The relative energy required to remove an
electron from different subshells of an atom or
ion or from the same subshell in different atoms
or ions (ionization energy) can be estimated
through a qualitative application of Coulomb’s
law. This energy is related to the distance from
the nucleus and the effective (shield) charge of
the nucleus.
Explain whether a model is
consistent with chemical
theories. 
Atoms and molecules can be identified by their electron distribution and energy. 
Explain the relationship
between the photoelectron
spectrum of an atom or
ion and:
a. The electron configuration
of the species.
b. The interactions
between the electrons
and the nucleus.
The energies of the electrons in a given
shell can be measured experimentally with
photoelectron spectroscopy (PES). The
position of each peak in the PES spectrum is
related to the energy required to remove an
electron from the corresponding subshell, and
the height of each peak is (ideally) proportional
to the number of electrons in that subshell.
Explain chemical properties
or phenomena (e.g., of
atoms or molecules)
using given chemical
theories, models, and
representations. 
The periodic table shows patterns in electronic structure and trends in
atomic properties.
Explain the relationship
between trends in atomic
properties of elements and
electronic structure
and periodicity. 
The organization of the periodic table is based
on the recurring properties of the elements and
explained by the pattern of electron configurations
and the presence of completely or partially filled
shells (and subshells) of electrons in atoms.
Trends in atomic properties within the
periodic table (periodicity) can be qualitatively
understood through the position of the element
in the periodic table, Coulomb’s law, the shell
model, and the concept of shielding/effective
nuclear charge. These properties include:
a. Ionization energy
b. Atomic and ionic radii
c. Electron affinity
d. Electronegativity
The periodicity is useful to
predict /estimate values of properties in the
absence of data.
Explain the connection
between particulatelevel and macroscopic
properties of a substance
using models and
representations.
The periodic table shows patterns in electronic structure and trends in
atomic properties. 
Explain the relationship
between trends in the
reactivity of elements
and periodicity
The likelihood that two elements will form
a chemical bond is determined by the
interactions between the valence electrons
and nuclei of elements.
Elements in the same column of the periodic
table tend to form analogous compounds.
Typical charges of atoms in ionic compounds
are governed by their location on the periodic
table and the number of valence electrons.