CHEM 219 Modules 1–8 Exams &
Final Exam – Principles of
Organic Chemistry (2026/2027)
| Portage Learning – Verified
Q&A
1. What is the formula used to calculate density?
Density = mass + volume
Density = mass - volume
Density = mass/volume
Density = volume/mass
2. A chemist has 18 grams of water (H2O). Using dimensional analysis, how
many moles of water does this correspond to? (Molar mass of H2O = 18
g/moll)
1 mole
2 moles
0.5 moles
3 moles
3. Explain why it is necessary to divide by the smallest number of moles when
calculating the empirical formula.
To simplify the ratio to whole numbers
To ensure the formula is balanced
To convert grams to moles
, To find the molecular weight of the compound
4. What does an orbital diagram illustrate regarding an atom?
The number of protons in the nucleus
The arrangement of electrons in orbitals
The mass of the atom
, The chemical properties of the element
5. Explain the difference in dissociation between strong acids and weak acids
in your own words.
Strong acids do not dissociate, while weak acids do.
Strong acids dissociate completely, whereas weak acids
dissociate only partially.
Both strong and weak acids dissociate completely.
Weak acids dissociate more than strong acids.
6. What are the substances called that undergo change during a chemical
reaction?
Products
Catalysts
Reactants
Solvents
7. What is the formula used to calculate the average atomic mass of an
element based on its isotopes?
Sum of isotopes' masses divided by the number of isotopes
Sum of isotopes' masses multiplied by their percent abundances
Sum of the products of each isotope's mass and its percent
abundance
Average of the isotopes' masses
8. Which three temperature units are commonly used in scientific contexts?
Fahrenheit, Celsius, Kelvin
Celsius, Rankine, Newton
Final Exam – Principles of
Organic Chemistry (2026/2027)
| Portage Learning – Verified
Q&A
1. What is the formula used to calculate density?
Density = mass + volume
Density = mass - volume
Density = mass/volume
Density = volume/mass
2. A chemist has 18 grams of water (H2O). Using dimensional analysis, how
many moles of water does this correspond to? (Molar mass of H2O = 18
g/moll)
1 mole
2 moles
0.5 moles
3 moles
3. Explain why it is necessary to divide by the smallest number of moles when
calculating the empirical formula.
To simplify the ratio to whole numbers
To ensure the formula is balanced
To convert grams to moles
, To find the molecular weight of the compound
4. What does an orbital diagram illustrate regarding an atom?
The number of protons in the nucleus
The arrangement of electrons in orbitals
The mass of the atom
, The chemical properties of the element
5. Explain the difference in dissociation between strong acids and weak acids
in your own words.
Strong acids do not dissociate, while weak acids do.
Strong acids dissociate completely, whereas weak acids
dissociate only partially.
Both strong and weak acids dissociate completely.
Weak acids dissociate more than strong acids.
6. What are the substances called that undergo change during a chemical
reaction?
Products
Catalysts
Reactants
Solvents
7. What is the formula used to calculate the average atomic mass of an
element based on its isotopes?
Sum of isotopes' masses divided by the number of isotopes
Sum of isotopes' masses multiplied by their percent abundances
Sum of the products of each isotope's mass and its percent
abundance
Average of the isotopes' masses
8. Which three temperature units are commonly used in scientific contexts?
Fahrenheit, Celsius, Kelvin
Celsius, Rankine, Newton
