CHEM 120 FINAL EXAM REVIEW EXAM
WITH CORRECT QUESTIONS AND
ANSWERS 2025
significant figures - CORRECT-ANSWERSa digit that is either reliably known or closely
estimated
Significant Figure Rules - CORRECT-ANSWERS1. 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-ANSWERSrelationship between two quantities expressed as a
fraction
,dimensional analysis - CORRECT-ANSWERSconversion of a measurement in one unit into
another by the use of conversion factors
True - CORRECT-ANSWERST/F: number of protons never changes according to periodic table
number of protons - CORRECT-ANSWERSatomic number=_______________________
number of neutrons - CORRECT-ANSWERSmass number=_______________________
isotopes - CORRECT-ANSWERSatoms with same number of protons (same electron) but
different number of neutrons
atomic mass - CORRECT-ANSWERSweighted average of the isotopic masses of all stable
isotopes of an element
compound - CORRECT-ANSWERSsubstance composed of 2+ elements that are chemically
combined
, molecular compound - CORRECT-ANSWERScompound in which atoms are held together by
covalent bonds
ionic bond - CORRECT-ANSWERSnonmetal and metal (giving away of electrons by one and
receiving by the other); electrostatic interactions between positive and negative ions
covalent bond - CORRECT-ANSWERS2 nonmetals (sharing of bonds); the sharing of electrons
between two atoms
ion - CORRECT-ANSWERSatom that has an electrostatic charge
cation - CORRECT-ANSWERSpositively charged atom
anion - CORRECT-ANSWERSnegatively charged atom
formula unit - CORRECT-ANSWERSsimplest whole number ratio of ions in ionic compound
polyatomic ion - CORRECT-ANSWERSgroups of covalently-bonded atoms that have an overall
charge
WITH CORRECT QUESTIONS AND
ANSWERS 2025
significant figures - CORRECT-ANSWERSa digit that is either reliably known or closely
estimated
Significant Figure Rules - CORRECT-ANSWERS1. 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-ANSWERSrelationship between two quantities expressed as a
fraction
,dimensional analysis - CORRECT-ANSWERSconversion of a measurement in one unit into
another by the use of conversion factors
True - CORRECT-ANSWERST/F: number of protons never changes according to periodic table
number of protons - CORRECT-ANSWERSatomic number=_______________________
number of neutrons - CORRECT-ANSWERSmass number=_______________________
isotopes - CORRECT-ANSWERSatoms with same number of protons (same electron) but
different number of neutrons
atomic mass - CORRECT-ANSWERSweighted average of the isotopic masses of all stable
isotopes of an element
compound - CORRECT-ANSWERSsubstance composed of 2+ elements that are chemically
combined
, molecular compound - CORRECT-ANSWERScompound in which atoms are held together by
covalent bonds
ionic bond - CORRECT-ANSWERSnonmetal and metal (giving away of electrons by one and
receiving by the other); electrostatic interactions between positive and negative ions
covalent bond - CORRECT-ANSWERS2 nonmetals (sharing of bonds); the sharing of electrons
between two atoms
ion - CORRECT-ANSWERSatom that has an electrostatic charge
cation - CORRECT-ANSWERSpositively charged atom
anion - CORRECT-ANSWERSnegatively charged atom
formula unit - CORRECT-ANSWERSsimplest whole number ratio of ions in ionic compound
polyatomic ion - CORRECT-ANSWERSgroups of covalently-bonded atoms that have an overall
charge
