CHEMISTRY FINAL ACS EXAM QUESTIONS
WITH COMPLETE AND CORRECTLY
SOLVED ANSWERS
Accuracy? Closeness of measurements to the TRUE VALUE of what is being
measured
Precision? Closeness of a SET of measurements
How do you calculate Percent Error? I experimental-accepted I
____________________ x 100 - accepted value
Are zeros in front of non-zero digits significant? Nope!
Ex: 0.0071 is only 2 sig figs
Are zeros at the end of a number and to the right of the decimal significant?
Yep! Ex: 9.100 is 4 sig figs
Addition/Subtraction in regards to sig figs? Round numbers to the least
number of decimal places
Multiplication/Division in regards to sig figs? Round answers to the least
amount of sig figs
# of e- equal
The # of p+
Atomic Mass? Number of protons in the nucleus (number on the left bottom
corner of the chemical symbol)
Atomic Mass Number? Number of protons and neutrons (number on the left
upper corner of the chemical symbol)
Isotope? Atoms of the same element, but with different masses (different
number of neutrons)
Which area of the Periodic Table has greater metallicness? Left and down
has greater metallicness
, Which area of the PT has greater atomic size? Left and down has a greater
atomic size
Which area of the PT has greater ionization energy? Right side and up has
greater ionization energy
Which area of the PT has greater electronegativity? Right side and up has
greater electronegativity, except the Noble Gases of 0 electronegativity
Ionic Bonding? Metal and nonmetal. Give/take electrons
Covalent bonding? Nonmetal and nonmetal. Share electrons.
VSEPR Theory? Valence Shell Electron Pair Repulsion aka Valence e- pairs
stay as far apart as possible
How do you determine polarity? Use the chart that has electronegativity
values, then subtract the elements in the compound from each other.
Is water polar? Yes!
Combination Reaction?
A + B --> AB
Decomposition Reaction?
AB --> A + B
Single Replacement Reaction?
AB + C --> AC + B
Double Replacement Reaction?
AB + CD --> AD + CB
Combustion Reaction?
C + H + O --> H2O + CO2 always
Avogadro's Number? 6.022 x 10^23 particles = 1 mole
Molar Mass? Gram/mole
Mole to Volume? 1 mole = 22.4 L
Empirical Formula vs Molecular Formula?
WITH COMPLETE AND CORRECTLY
SOLVED ANSWERS
Accuracy? Closeness of measurements to the TRUE VALUE of what is being
measured
Precision? Closeness of a SET of measurements
How do you calculate Percent Error? I experimental-accepted I
____________________ x 100 - accepted value
Are zeros in front of non-zero digits significant? Nope!
Ex: 0.0071 is only 2 sig figs
Are zeros at the end of a number and to the right of the decimal significant?
Yep! Ex: 9.100 is 4 sig figs
Addition/Subtraction in regards to sig figs? Round numbers to the least
number of decimal places
Multiplication/Division in regards to sig figs? Round answers to the least
amount of sig figs
# of e- equal
The # of p+
Atomic Mass? Number of protons in the nucleus (number on the left bottom
corner of the chemical symbol)
Atomic Mass Number? Number of protons and neutrons (number on the left
upper corner of the chemical symbol)
Isotope? Atoms of the same element, but with different masses (different
number of neutrons)
Which area of the Periodic Table has greater metallicness? Left and down
has greater metallicness
, Which area of the PT has greater atomic size? Left and down has a greater
atomic size
Which area of the PT has greater ionization energy? Right side and up has
greater ionization energy
Which area of the PT has greater electronegativity? Right side and up has
greater electronegativity, except the Noble Gases of 0 electronegativity
Ionic Bonding? Metal and nonmetal. Give/take electrons
Covalent bonding? Nonmetal and nonmetal. Share electrons.
VSEPR Theory? Valence Shell Electron Pair Repulsion aka Valence e- pairs
stay as far apart as possible
How do you determine polarity? Use the chart that has electronegativity
values, then subtract the elements in the compound from each other.
Is water polar? Yes!
Combination Reaction?
A + B --> AB
Decomposition Reaction?
AB --> A + B
Single Replacement Reaction?
AB + C --> AC + B
Double Replacement Reaction?
AB + CD --> AD + CB
Combustion Reaction?
C + H + O --> H2O + CO2 always
Avogadro's Number? 6.022 x 10^23 particles = 1 mole
Molar Mass? Gram/mole
Mole to Volume? 1 mole = 22.4 L
Empirical Formula vs Molecular Formula?
