PCAT Chemistry 100% complete exam
Atomic Number - ANSWERSNumber of Protons, Electrons
Mass Number - ANSWERSTotal number of Protons and Neutrons
Valence Electrons - ANSWERSElectrons farthest from the nucleus
Ion - ANSWERSA positive or negative charge to an atom due to a loss or gain of
electrons
Atomic Weight - ANSWERSWeight in grams of one mole of a given element
Mole - ANSWERS6.022 x 10²³ particles of an element
Isotope - ANSWERSMultiple species of atoms with the same number of protons but
different numbers of neutrons
Angular Momentum - ANSWERS(nh)/(2π)
n = quantum number that can be any positive integer
h = Plank's constant (6.626 x 10ˉ³⁴ J•s)
Principal Quantum Number - ANSWERSFirst quantum number, designated n.
Azimuthal Quantum Number - ANSWERSSecond quantum number, designated l. Tells
us the shapes of the electron orbitals
Magnetic Quantum Number - ANSWERSThird quantum number, designated m(ϑ).
Tells us the orientation of the orbitals
(n+l) rule - ANSWERSUsed to rank subshells by increasing energy
Periodic Trend for atomic radii - ANSWERSDecreases left to right, increases down
Periodic Trend for electronegativity - ANSWERSIncreases left to right, decreases down
3 types of elements - ANSWERSmetals - located on the left and middle
nonmetals - located on the right side
metalloids - found along a diagonal line between the other two
Type of Reaction: S + O₂ → SO₂ - ANSWERSCombination Reaction
Type of Reaction: 2 HgO → 2 Hg + O₂ - ANSWERSDecomposition Reaction
, Type of Reaction: Zn + CuSO₄ → Cu + ZnSO₄ - ANSWERSSingle Displacement
Reaction
Type of Reaction: CaCl₂ + 2 AgNO₃ → Ca(NO₃)₂ + 2 AgCl - ANSWERSDouble
Displacement Reaction
Percent Yield - ANSWERS(Actual Yield/Theoretical Yield) x 100%
Rank the intermolecular forces from strongest to weakest - ANSWERSdipole ion >
hydrogen bonding > dipole-dipole > dispersion (London) forces
% Composition - ANSWERS(Mass of X in formula)/(Formula Weight of Compound) x
100%
Used to determine the number of moles present - ANSWERSMol = (weight of sample
(g))/(Molar weight (g/mol))
For aA + bB → cC + dD: Rate = ? - ANSWERSk[A]^x • [B]^y
x & y must be determined experimentally
Order of Reaction - ANSWERSDetermined by adding the exponents of the rate of the
equation r = k[A]^x • [B]^y
Rate of Zero-order reaction - ANSWERSconstant rate of r = k
Rate of First-order reaction - ANSWERSproportional to the concentration of one
reactant.
rate = k[A] or rate = k[B]
Classic example of First-order reaction - ANSWERSProcess of radioactive decay
Calculation for determining a half-life - ANSWERSt½ = ln 2/k = 0.693/k
Rate of Second-order reaction - ANSWERSproportional to the product of the
concentration of two reactants or to the square of the concentration of a single reactant.
rate = k[A]², rate = k[B]², or rate = k[A][B]
Activation Energy - ANSWERSThe minimum energy of collision necessary for a
reaction to take place
Enthalpy Change - ANSWERSThe difference between the potential energy of the
products and the potential energy of the reactants
A negative enthalpy change indicates... - ANSWERSexothermic reaction
A positive enthalpy change indicates... - ANSWERSendothermic reaction
Atomic Number - ANSWERSNumber of Protons, Electrons
Mass Number - ANSWERSTotal number of Protons and Neutrons
Valence Electrons - ANSWERSElectrons farthest from the nucleus
Ion - ANSWERSA positive or negative charge to an atom due to a loss or gain of
electrons
Atomic Weight - ANSWERSWeight in grams of one mole of a given element
Mole - ANSWERS6.022 x 10²³ particles of an element
Isotope - ANSWERSMultiple species of atoms with the same number of protons but
different numbers of neutrons
Angular Momentum - ANSWERS(nh)/(2π)
n = quantum number that can be any positive integer
h = Plank's constant (6.626 x 10ˉ³⁴ J•s)
Principal Quantum Number - ANSWERSFirst quantum number, designated n.
Azimuthal Quantum Number - ANSWERSSecond quantum number, designated l. Tells
us the shapes of the electron orbitals
Magnetic Quantum Number - ANSWERSThird quantum number, designated m(ϑ).
Tells us the orientation of the orbitals
(n+l) rule - ANSWERSUsed to rank subshells by increasing energy
Periodic Trend for atomic radii - ANSWERSDecreases left to right, increases down
Periodic Trend for electronegativity - ANSWERSIncreases left to right, decreases down
3 types of elements - ANSWERSmetals - located on the left and middle
nonmetals - located on the right side
metalloids - found along a diagonal line between the other two
Type of Reaction: S + O₂ → SO₂ - ANSWERSCombination Reaction
Type of Reaction: 2 HgO → 2 Hg + O₂ - ANSWERSDecomposition Reaction
, Type of Reaction: Zn + CuSO₄ → Cu + ZnSO₄ - ANSWERSSingle Displacement
Reaction
Type of Reaction: CaCl₂ + 2 AgNO₃ → Ca(NO₃)₂ + 2 AgCl - ANSWERSDouble
Displacement Reaction
Percent Yield - ANSWERS(Actual Yield/Theoretical Yield) x 100%
Rank the intermolecular forces from strongest to weakest - ANSWERSdipole ion >
hydrogen bonding > dipole-dipole > dispersion (London) forces
% Composition - ANSWERS(Mass of X in formula)/(Formula Weight of Compound) x
100%
Used to determine the number of moles present - ANSWERSMol = (weight of sample
(g))/(Molar weight (g/mol))
For aA + bB → cC + dD: Rate = ? - ANSWERSk[A]^x • [B]^y
x & y must be determined experimentally
Order of Reaction - ANSWERSDetermined by adding the exponents of the rate of the
equation r = k[A]^x • [B]^y
Rate of Zero-order reaction - ANSWERSconstant rate of r = k
Rate of First-order reaction - ANSWERSproportional to the concentration of one
reactant.
rate = k[A] or rate = k[B]
Classic example of First-order reaction - ANSWERSProcess of radioactive decay
Calculation for determining a half-life - ANSWERSt½ = ln 2/k = 0.693/k
Rate of Second-order reaction - ANSWERSproportional to the product of the
concentration of two reactants or to the square of the concentration of a single reactant.
rate = k[A]², rate = k[B]², or rate = k[A][B]
Activation Energy - ANSWERSThe minimum energy of collision necessary for a
reaction to take place
Enthalpy Change - ANSWERSThe difference between the potential energy of the
products and the potential energy of the reactants
A negative enthalpy change indicates... - ANSWERSexothermic reaction
A positive enthalpy change indicates... - ANSWERSendothermic reaction
