CHEM 104 FINAL EXAM QUESTIONS
AND ANSWERS. VERIFIED 2026.
A sample of aluminum contains 2.91 × 1022 atoms of aluminum. What is the mass of this
sample? [Molar mass: Al, 26.98 g/mol] - ANS 1.30 g
What is the number 3,000 written in scientific notation using the proper number of significant
figures? - ANS 3 × 10^3
Which statement about the modern periodic table is FALSE? - ANS Elements in the same
period share similar chemical and physical properties.
Which of the following is NOT a unit for measuring pressure? - ANS kJ
A covalent bond involves which of the following? - ANS sharing of electrons between two
atoms
Which statement correctly describes what is happening in the reaction shown below?
2Mg(s) + S2(g) → MgS(s) - ANS Mg is oxidized.
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,Which statement explains why isotopes have different mass numbers? - ANS Isotopes differ
in the number of neutrons each contains
Enough water is added to 50.0 mL of a 0.660 M NaOH solution in order to bring the total
volume to 450.0 mL. What is the molarity of this diluted solution? - ANS 0.0733 M
The unbalanced equation for the combustion of octane, a component of gasoline, is shown
below. What would be the coefficient of carbon dioxide once the equation is balanced?
C8H18(l) + O2(g) → CO2(g) + H2O(l) - ANS 16
When a neutral atom gains one or more electrons, what type of particle is formed? - ANS an
anion
What is the name of the ionic compound with the formula Na3PO4? - ANS sodium phosphate
What law predicts the expansion of a balloon when helium is added? - ANS Avogadro's Law
Methanol (CH3OH) is the fuel used by racecars in the Indianapolis 500. It burns in the engine
according to the equation below. How many moles of oxygen gas are necessary to react
completely with 12.5 L of methanol? [Density: CH3OH, 0.7910g/mL; Molar mass: CH3OH, 32.05
g/mol]
2CH3OH(l) + 3O2(g) → 2CO2(g) + 4H2O(g) - ANS 463 mol
At what temperature is a liquid converted into a gas? - ANS the boiling point of the liquid
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, The drug "lithium" is often prescribed to treat mental illness. It is not the element lithium, but
the ionic compound Li2CO3, that is actually administered. What is the name of this compound?
- ANS lithium carbonateConsider the chemical equation shown below. How many moles of
oxygen gas are needed to react with hydrogen to form one mole of water? 2H2(g) + O2(g) →
2H2O(l)
Hydrogen fluoride will react with glass (silicon dioxide, SiO2) according to the equation below.
What mass of HF is required to react completely with 16.0 g of glass? [Molar masses: Si, 28.09
g/mol; F, 19.00 g/mol; H, 1.01 g/mol; O, 16.00 g/mol]
4HF(g) + SiO2(s) → SiF4(g) + 2H2O(g) - ANS 21.3 g
Two molecules of ethane experience what type of attractive forces? - ANS London forces
A solution contains the label 0.2 M KNO3. What is the correct interpretation of this
concentration? - ANS There are 0.2 moles of KNO3 in 1 L of solution.
Which properly represents the Lewis structure of hydrogen sulfide, H2S? - ANS
If 5.20 g of HCl is added to enough distilled water to form 3.00 L of solution, what is the molarity
of the solution? [Molecular weight: HCl, 36.46 amu] - ANS 0.0475 M
A patient needs 0.300 g of a solid drug preparation per day. How many 10.0 mg tablets must be
given to the patient per day? - ANS 30.0 tablets
What term is used to describe atoms of the same element that have different masses? -
ANS isotopes
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
AND ANSWERS. VERIFIED 2026.
A sample of aluminum contains 2.91 × 1022 atoms of aluminum. What is the mass of this
sample? [Molar mass: Al, 26.98 g/mol] - ANS 1.30 g
What is the number 3,000 written in scientific notation using the proper number of significant
figures? - ANS 3 × 10^3
Which statement about the modern periodic table is FALSE? - ANS Elements in the same
period share similar chemical and physical properties.
Which of the following is NOT a unit for measuring pressure? - ANS kJ
A covalent bond involves which of the following? - ANS sharing of electrons between two
atoms
Which statement correctly describes what is happening in the reaction shown below?
2Mg(s) + S2(g) → MgS(s) - ANS Mg is oxidized.
1 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
,Which statement explains why isotopes have different mass numbers? - ANS Isotopes differ
in the number of neutrons each contains
Enough water is added to 50.0 mL of a 0.660 M NaOH solution in order to bring the total
volume to 450.0 mL. What is the molarity of this diluted solution? - ANS 0.0733 M
The unbalanced equation for the combustion of octane, a component of gasoline, is shown
below. What would be the coefficient of carbon dioxide once the equation is balanced?
C8H18(l) + O2(g) → CO2(g) + H2O(l) - ANS 16
When a neutral atom gains one or more electrons, what type of particle is formed? - ANS an
anion
What is the name of the ionic compound with the formula Na3PO4? - ANS sodium phosphate
What law predicts the expansion of a balloon when helium is added? - ANS Avogadro's Law
Methanol (CH3OH) is the fuel used by racecars in the Indianapolis 500. It burns in the engine
according to the equation below. How many moles of oxygen gas are necessary to react
completely with 12.5 L of methanol? [Density: CH3OH, 0.7910g/mL; Molar mass: CH3OH, 32.05
g/mol]
2CH3OH(l) + 3O2(g) → 2CO2(g) + 4H2O(g) - ANS 463 mol
At what temperature is a liquid converted into a gas? - ANS the boiling point of the liquid
2 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
, The drug "lithium" is often prescribed to treat mental illness. It is not the element lithium, but
the ionic compound Li2CO3, that is actually administered. What is the name of this compound?
- ANS lithium carbonateConsider the chemical equation shown below. How many moles of
oxygen gas are needed to react with hydrogen to form one mole of water? 2H2(g) + O2(g) →
2H2O(l)
Hydrogen fluoride will react with glass (silicon dioxide, SiO2) according to the equation below.
What mass of HF is required to react completely with 16.0 g of glass? [Molar masses: Si, 28.09
g/mol; F, 19.00 g/mol; H, 1.01 g/mol; O, 16.00 g/mol]
4HF(g) + SiO2(s) → SiF4(g) + 2H2O(g) - ANS 21.3 g
Two molecules of ethane experience what type of attractive forces? - ANS London forces
A solution contains the label 0.2 M KNO3. What is the correct interpretation of this
concentration? - ANS There are 0.2 moles of KNO3 in 1 L of solution.
Which properly represents the Lewis structure of hydrogen sulfide, H2S? - ANS
If 5.20 g of HCl is added to enough distilled water to form 3.00 L of solution, what is the molarity
of the solution? [Molecular weight: HCl, 36.46 amu] - ANS 0.0475 M
A patient needs 0.300 g of a solid drug preparation per day. How many 10.0 mg tablets must be
given to the patient per day? - ANS 30.0 tablets
What term is used to describe atoms of the same element that have different masses? -
ANS isotopes
3 @COPYRIGHT 2025/2026 ALLRIGHTS RESERVED.
