CHEM 120 Final Exam Review Question
and answers verified to pass 2025
significant figures - correct answer ✔a digit that is either reliably known or
closely estimated
Significant Figure Rules - correct answer ✔1. All non-zero digits are always
significant
2. Zeroes between non-zero digits are always significant
3. Zeroes to left of first non-zero digit (either before or after decimal point) are
never significant
4. Zeroes to the right of last non-zero digit
a. after decimal point are always significant
b. which are before decimal point are not significant
conversion factor - correct answer ✔relationship between two quantities
expressed as a fraction
dimensional analysis - correct answer ✔conversion of a measurement in one
unit into another by the use of conversion factors
True - correct answer ✔T/F: number of protons never changes according to
periodic table
number of protons - correct answer ✔atomic
number=_______________________
, number of neutrons - correct answer ✔mass
number=_______________________
isotopes - correct answer ✔atoms with same number of protons (same
electron) but different number of neutrons
atomic mass - correct answer ✔weighted average of the isotopic masses of
all stable isotopes of an element
compound - correct answer ✔substance composed of 2+ elements that are
chemically combined
molecular compound - correct answer ✔compound in which atoms are held
together by covalent bonds
ionic bond - correct answer ✔nonmetal and metal (giving away of electrons
by one and receiving by the other); electrostatic interactions between positive
and negative ions
covalent bond - correct answer ✔2 nonmetals (sharing of bonds); the sharing
of electrons between two atoms
ion - correct answer ✔atom that has an electrostatic charge
cation - correct answer ✔positively charged atom
anion - correct answer ✔negatively charged atom
and answers verified to pass 2025
significant figures - correct answer ✔a digit that is either reliably known or
closely estimated
Significant Figure Rules - correct answer ✔1. All non-zero digits are always
significant
2. Zeroes between non-zero digits are always significant
3. Zeroes to left of first non-zero digit (either before or after decimal point) are
never significant
4. Zeroes to the right of last non-zero digit
a. after decimal point are always significant
b. which are before decimal point are not significant
conversion factor - correct answer ✔relationship between two quantities
expressed as a fraction
dimensional analysis - correct answer ✔conversion of a measurement in one
unit into another by the use of conversion factors
True - correct answer ✔T/F: number of protons never changes according to
periodic table
number of protons - correct answer ✔atomic
number=_______________________
, number of neutrons - correct answer ✔mass
number=_______________________
isotopes - correct answer ✔atoms with same number of protons (same
electron) but different number of neutrons
atomic mass - correct answer ✔weighted average of the isotopic masses of
all stable isotopes of an element
compound - correct answer ✔substance composed of 2+ elements that are
chemically combined
molecular compound - correct answer ✔compound in which atoms are held
together by covalent bonds
ionic bond - correct answer ✔nonmetal and metal (giving away of electrons
by one and receiving by the other); electrostatic interactions between positive
and negative ions
covalent bond - correct answer ✔2 nonmetals (sharing of bonds); the sharing
of electrons between two atoms
ion - correct answer ✔atom that has an electrostatic charge
cation - correct answer ✔positively charged atom
anion - correct answer ✔negatively charged atom
