AP Chemistry Exam Review Questions
With Correct Answers
atomic number - CORRECT ANSWER✔✔-The same as the number of protons in
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the nucleus of an element; it is also the same as the number of electrons
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surrounding the nucleus of an element when it is neutrally charged.
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mass number - CORRECT ANSWER✔✔-The sum of an atom's neutrons and
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protons
isotopes - CORRECT ANSWER✔✔-Atoms of an element with different numbers of
| | | | | | | | | | |
neutrons
Avogadro's number - CORRECT ANSWER✔✔-6.022×10²³ particles per one mole
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Moles - CORRECT ANSWER✔✔-grams/molar mass
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Standard Temperature and Pressure (STP) - CORRECT ANSWER✔✔-Pressure = 1
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atm
Temperature = 273 K | | |
Converting from moles to liters - CORRECT ANSWER✔✔-I mole of gas = 22.4 L
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Moles and Solutions - CORRECT ANSWER✔✔-Moles = (molarity)(liters of solution)
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,percent composition (mass percents) - CORRECT ANSWER✔✔-The percent by
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mass of each element that makes up a compound. It is calculated by dividing the
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mass of each element or component in a compound by the total molar mass for
| | | | | | | | | | | | | | |
the substance.
|
empirical formula - CORRECT ANSWER✔✔-- Represents the simplest ratio of one
| | | | | | | | | | |
element to another in a compound | | | | |
- Start by assuming a 100 g sample
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- Convert percentages to grams
| | | |
- Convert grams into moles
| | | |
- Divide each mole value by the lowest of the values
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- These values become the subscripts
| | | | |
molecular formula - CORRECT ANSWER✔✔-- Determine the molar mass of the
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empirical formula |
- Divide that mass into the molar mass
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x = m/e
| |
x = molar mass/ empirical mass
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- Multiply all subscripts in the empirical formula by the value of x
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Aufbau principle - CORRECT ANSWER✔✔-States that when building up the
| | | | | | | | | |
electron configuration of an atom, electrons are placed in orbitals, subshells, and
| | | | | | | | | | | |
shells in order of increasing energy.
| | | | |
,Pauli Exclusion Principle - CORRECT ANSWER✔✔-States that the two electrons
| | | | | | | | | |
which share an orbital cannot have the same spin. One electron must spin
| | | | | | | | | | | | |
clockwise, and the other must spin counterclockwise.
| | | | | |
Hund's Rule - CORRECT ANSWER✔✔-States that when an electron is added to a
| | | | | | | | | | | | |
subshell, it will always occupy an empty orbital if no one is available. Electrons
| | | | | | | | | | | | | |
always occupy orbitals singly if possible and pair up only if no empty orbitals are
| | | | | | | | | | | | | | |
available.
Coulomb's Law - CORRECT ANSWER✔✔-The amount of energy that an electron
| | | | | | | | | | |
has depends on its distance from nucleus of an atom. While on the exam, you will
| | | | | | | | | | | | | | |
not be required to mathematically calculate the amount of energy a given
| | | | | | | | | | | | |
electron has, you should be able to qualitatively apply Coulomb's Law.
| | | | | | | | | | |
Essentially, the greater the charge of the nucleus, the more energy an electron
| | | | | | | | | | | | |
will have.
|
Quantum Theory - CORRECT ANSWER✔✔-Max Planck figured out that
| | | | | | | | |
electromagnetic energy is quantized. That is, for a given frequency of radiation
| | | | | | | | | | | |
(or light), all possible energies are multiples of a certain unit of energy, called a
| | | | | | | | | | | | | | |
quantum (mathematically, that's E = hv). So, energy changes do not occur
| | | | | | | | | | | |
smoothly but rather in small but specific steps.
| | | | | | |
Energy and Electromagnetic Radiation - CORRECT ANSWER✔✔-ΔE = hv = hc/λ
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ΔE = energy change
| | |
, h = Planck's constant, 6.626×10⁻³⁴ J∙s
| | | | |
v = frequency of the radiation
| | | | |
λ = wavelength of the radiation
| | | | |
c = the speed of light, 3.00×10⁸ m/s
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Frequency and Wavelength - CORRECT ANSWER✔✔-c = λv
| | | | | | |
*Inversely proportional* |
c = speed of light in a vacuum (2.998×10⁸ m/s)
| | | | | | | | |
λ = wavelength of the radiation
| | | | |
v = frequency of the radiation
| | | | |
ionization energy - CORRECT ANSWER✔✔-The amount of energy necessary to
| | | | | | | | | |
remove an electron from an atom.
| | | | |
photoelectron spectra (PES) - CORRECT ANSWER✔✔-A chart of the amount of
| | | | | | | | | | |
ionization energy for all electrons ejected from a nucleus.
| | | | | | | |
The y-axis describes the relative number of electrons that are ejected from a
| | | | | | | | | | | | |
given energy level.
| |
The x-axis shows the binding energy of those electrons.
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With Correct Answers
atomic number - CORRECT ANSWER✔✔-The same as the number of protons in
| | | | | | | | | | | |
the nucleus of an element; it is also the same as the number of electrons
| | | | | | | | | | | | | | |
surrounding the nucleus of an element when it is neutrally charged.
| | | | | | | | | |
mass number - CORRECT ANSWER✔✔-The sum of an atom's neutrons and
| | | | | | | | | | |
protons
isotopes - CORRECT ANSWER✔✔-Atoms of an element with different numbers of
| | | | | | | | | | |
neutrons
Avogadro's number - CORRECT ANSWER✔✔-6.022×10²³ particles per one mole
| | | | | | | |
Moles - CORRECT ANSWER✔✔-grams/molar mass
| | | |
Standard Temperature and Pressure (STP) - CORRECT ANSWER✔✔-Pressure = 1
| | | | | | | | | |
atm
Temperature = 273 K | | |
Converting from moles to liters - CORRECT ANSWER✔✔-I mole of gas = 22.4 L
| | | | | | | | | | | | |
Moles and Solutions - CORRECT ANSWER✔✔-Moles = (molarity)(liters of solution)
| | | | | | | | |
,percent composition (mass percents) - CORRECT ANSWER✔✔-The percent by
| | | | | | | | |
mass of each element that makes up a compound. It is calculated by dividing the
| | | | | | | | | | | | | | |
mass of each element or component in a compound by the total molar mass for
| | | | | | | | | | | | | | |
the substance.
|
empirical formula - CORRECT ANSWER✔✔-- Represents the simplest ratio of one
| | | | | | | | | | |
element to another in a compound | | | | |
- Start by assuming a 100 g sample
| | | | | | |
- Convert percentages to grams
| | | |
- Convert grams into moles
| | | |
- Divide each mole value by the lowest of the values
| | | | | | | | | |
- These values become the subscripts
| | | | |
molecular formula - CORRECT ANSWER✔✔-- Determine the molar mass of the
| | | | | | | | | | |
empirical formula |
- Divide that mass into the molar mass
| | | | | | |
x = m/e
| |
x = molar mass/ empirical mass
| | | | |
- Multiply all subscripts in the empirical formula by the value of x
| | | | | | | | | | | |
Aufbau principle - CORRECT ANSWER✔✔-States that when building up the
| | | | | | | | | |
electron configuration of an atom, electrons are placed in orbitals, subshells, and
| | | | | | | | | | | |
shells in order of increasing energy.
| | | | |
,Pauli Exclusion Principle - CORRECT ANSWER✔✔-States that the two electrons
| | | | | | | | | |
which share an orbital cannot have the same spin. One electron must spin
| | | | | | | | | | | | |
clockwise, and the other must spin counterclockwise.
| | | | | |
Hund's Rule - CORRECT ANSWER✔✔-States that when an electron is added to a
| | | | | | | | | | | | |
subshell, it will always occupy an empty orbital if no one is available. Electrons
| | | | | | | | | | | | | |
always occupy orbitals singly if possible and pair up only if no empty orbitals are
| | | | | | | | | | | | | | |
available.
Coulomb's Law - CORRECT ANSWER✔✔-The amount of energy that an electron
| | | | | | | | | | |
has depends on its distance from nucleus of an atom. While on the exam, you will
| | | | | | | | | | | | | | |
not be required to mathematically calculate the amount of energy a given
| | | | | | | | | | | | |
electron has, you should be able to qualitatively apply Coulomb's Law.
| | | | | | | | | | |
Essentially, the greater the charge of the nucleus, the more energy an electron
| | | | | | | | | | | | |
will have.
|
Quantum Theory - CORRECT ANSWER✔✔-Max Planck figured out that
| | | | | | | | |
electromagnetic energy is quantized. That is, for a given frequency of radiation
| | | | | | | | | | | |
(or light), all possible energies are multiples of a certain unit of energy, called a
| | | | | | | | | | | | | | |
quantum (mathematically, that's E = hv). So, energy changes do not occur
| | | | | | | | | | | |
smoothly but rather in small but specific steps.
| | | | | | |
Energy and Electromagnetic Radiation - CORRECT ANSWER✔✔-ΔE = hv = hc/λ
| | | | | | | | | |
ΔE = energy change
| | |
, h = Planck's constant, 6.626×10⁻³⁴ J∙s
| | | | |
v = frequency of the radiation
| | | | |
λ = wavelength of the radiation
| | | | |
c = the speed of light, 3.00×10⁸ m/s
| | | | | | |
Frequency and Wavelength - CORRECT ANSWER✔✔-c = λv
| | | | | | |
*Inversely proportional* |
c = speed of light in a vacuum (2.998×10⁸ m/s)
| | | | | | | | |
λ = wavelength of the radiation
| | | | |
v = frequency of the radiation
| | | | |
ionization energy - CORRECT ANSWER✔✔-The amount of energy necessary to
| | | | | | | | | |
remove an electron from an atom.
| | | | |
photoelectron spectra (PES) - CORRECT ANSWER✔✔-A chart of the amount of
| | | | | | | | | | |
ionization energy for all electrons ejected from a nucleus.
| | | | | | | |
The y-axis describes the relative number of electrons that are ejected from a
| | | | | | | | | | | | |
given energy level.
| |
The x-axis shows the binding energy of those electrons.
| | | | | | | |
