Principles of Chemistry 1 University of Iowa
Final Complete 2026–2027 Exam Preparation
Guide: Updated Question Bank, Explained
Solutions, Concept Review & Effective Study
Strategies
Description
The Complete 2026–2027 Exam Preparation Guide is a
structured and reliable resource developed to support
students in achieving better academic outcomes through
focused practice, clear explanations, and organized
revision.
This guide is designed to bridge the gap between learning
concepts and applying them in exams. By combining a
wide range of practice questions with clearly explained
solutions, it helps students understand not only the correct
answers but also the methods required to solve similar
problems independently.
Sig Figs - ANSWER✅1) All nonzero digits are significant
2) zeroes between nonzero digits are always significant
3)zeroes at the beginning of a number are never significant
,4)zeros at the end of the number are significant if the number contains a decimal point.
adding and subtracting sig figs - ANSWER✅same number of decimal places as the
measurement with fewest decimal places.
50.61+4.338+208.2= 263.148
sooo... 263.1
multiplying and dividing sig figs - ANSWER✅same number of sig figs as the
measurement with fewest sig figs
6.221 x 5.2= 32.3492
sooo... 32
Empedocles - ANSWER✅Q: Are there fundamental Substances?
A: yes, air, fire, water
Democritus - ANSWER✅Q: Is matter continuous or particulate?
A: Particulate ("atom" from Greek atomos= indivisible)
John Dalton - ANSWER✅Daltons Atomic Theory
1) All matter consists of tiny indivisible atoms.
2) Atoms of an element are identical, but different from those other elements
3) Atoms of one element cannot be converted into those of another element.
4) Compounds result from chemical combinations of different elements; atom ratios are
integers.
Law Of Conservation of Mass - ANSWER✅mass of one side of the equation equals
mass of the other side
Law of Constant Composition - ANSWER✅In a compound the relative numbers and
kinds of atoms are constant ex: water is always H2O
Law of Multiple Proportions - ANSWER✅ratios are small whole numbers
Are John Dalton's Postulates always true? - ANSWER✅Nope!
-isotopes exist etc.
J.J Thomson - ANSWER✅-cathode rays are independent of the electrode material
-Cathode rays are streams of negatively charged particles (now called electrons)
Robert Millikan - ANSWER✅Oil Drop experiment
-caused oil drops to become charged and observed their behavior in an electric
field.This led to charge of electron
Thomson's Plum Pudding Model - ANSWER✅Evenly distributed mass and positive
charge (cookie)
, Small embedded negative particles (chocolate chips)
Ernest Rutherford - ANSWER✅discovered nature of radioactivity
Proposed nuclear atom as:
-very small, dense, positive nucleus
-surrounded by negative electrons
Rutherford's Gold Foil experiment - ANSWER✅studied angles at which alpha particles
were scattered after passing through thin gold foil
-disproved plum pudding modelof atom
Isotopes - ANSWER✅atoms with identical atomic numbers (same number of protons)
but different mass numbers (different # of neutrons)
-atomic number (z)= number of protons
-mass number (A)= number of protons+ neutrons
atomic mass - ANSWER✅mass of a single atom in atomic mass units (amu)
mass spectrometer - ANSWER✅instrument that can determine very accurate mass
measurements and isotopic abundance
atomic weight - ANSWER✅average atomic mass of all of the isotopes of an element
weighted by the relative abundance of each isotope expressed in amu.
The seven diatomic molecules - ANSWER✅H,O,N,F,Cl,Br,I
Molecular Compound - ANSWER✅contain only non metals of metalloids
Ions - ANSWER✅formed when atoms gain or lose electrons
cation - ANSWER✅positive ion formed when electrons are lost
anion - ANSWER✅negative ion formed when electrons are gained
Ion trend - ANSWER✅metals tend to form cations and nonmetals tend to form anions
Ammonium - ANSWER✅
Cyanide - ANSWER✅
Hydroxide - ANSWER✅
Final Complete 2026–2027 Exam Preparation
Guide: Updated Question Bank, Explained
Solutions, Concept Review & Effective Study
Strategies
Description
The Complete 2026–2027 Exam Preparation Guide is a
structured and reliable resource developed to support
students in achieving better academic outcomes through
focused practice, clear explanations, and organized
revision.
This guide is designed to bridge the gap between learning
concepts and applying them in exams. By combining a
wide range of practice questions with clearly explained
solutions, it helps students understand not only the correct
answers but also the methods required to solve similar
problems independently.
Sig Figs - ANSWER✅1) All nonzero digits are significant
2) zeroes between nonzero digits are always significant
3)zeroes at the beginning of a number are never significant
,4)zeros at the end of the number are significant if the number contains a decimal point.
adding and subtracting sig figs - ANSWER✅same number of decimal places as the
measurement with fewest decimal places.
50.61+4.338+208.2= 263.148
sooo... 263.1
multiplying and dividing sig figs - ANSWER✅same number of sig figs as the
measurement with fewest sig figs
6.221 x 5.2= 32.3492
sooo... 32
Empedocles - ANSWER✅Q: Are there fundamental Substances?
A: yes, air, fire, water
Democritus - ANSWER✅Q: Is matter continuous or particulate?
A: Particulate ("atom" from Greek atomos= indivisible)
John Dalton - ANSWER✅Daltons Atomic Theory
1) All matter consists of tiny indivisible atoms.
2) Atoms of an element are identical, but different from those other elements
3) Atoms of one element cannot be converted into those of another element.
4) Compounds result from chemical combinations of different elements; atom ratios are
integers.
Law Of Conservation of Mass - ANSWER✅mass of one side of the equation equals
mass of the other side
Law of Constant Composition - ANSWER✅In a compound the relative numbers and
kinds of atoms are constant ex: water is always H2O
Law of Multiple Proportions - ANSWER✅ratios are small whole numbers
Are John Dalton's Postulates always true? - ANSWER✅Nope!
-isotopes exist etc.
J.J Thomson - ANSWER✅-cathode rays are independent of the electrode material
-Cathode rays are streams of negatively charged particles (now called electrons)
Robert Millikan - ANSWER✅Oil Drop experiment
-caused oil drops to become charged and observed their behavior in an electric
field.This led to charge of electron
Thomson's Plum Pudding Model - ANSWER✅Evenly distributed mass and positive
charge (cookie)
, Small embedded negative particles (chocolate chips)
Ernest Rutherford - ANSWER✅discovered nature of radioactivity
Proposed nuclear atom as:
-very small, dense, positive nucleus
-surrounded by negative electrons
Rutherford's Gold Foil experiment - ANSWER✅studied angles at which alpha particles
were scattered after passing through thin gold foil
-disproved plum pudding modelof atom
Isotopes - ANSWER✅atoms with identical atomic numbers (same number of protons)
but different mass numbers (different # of neutrons)
-atomic number (z)= number of protons
-mass number (A)= number of protons+ neutrons
atomic mass - ANSWER✅mass of a single atom in atomic mass units (amu)
mass spectrometer - ANSWER✅instrument that can determine very accurate mass
measurements and isotopic abundance
atomic weight - ANSWER✅average atomic mass of all of the isotopes of an element
weighted by the relative abundance of each isotope expressed in amu.
The seven diatomic molecules - ANSWER✅H,O,N,F,Cl,Br,I
Molecular Compound - ANSWER✅contain only non metals of metalloids
Ions - ANSWER✅formed when atoms gain or lose electrons
cation - ANSWER✅positive ion formed when electrons are lost
anion - ANSWER✅negative ion formed when electrons are gained
Ion trend - ANSWER✅metals tend to form cations and nonmetals tend to form anions
Ammonium - ANSWER✅
Cyanide - ANSWER✅
Hydroxide - ANSWER✅
