Chem 104 Final Exam 2024.
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]
1.30 g
What is the number 3,000 written in scientific notation using the proper number of significant figures?
3 × 10^3
Which statement about the modern periodic table is FALSE?
Elements in the same period share similar chemical and physical properties.
Which of the following is NOT a unit for measuring pressure?
kJ
A covalent bond involves which of the following?
sharing of electrons between two atoms
Which statement correctly describes what is happening in the reaction shown below?
2Mg(s) + S2(g) → MgS(s)
Mg is oxidized.
Which statement explains why isotopes have different mass numbers?
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?
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)
16
When a neutral atom gains one or more electrons, what type of particle is formed?
an anion
What is the name of the ionic compound with the formula Na3PO4?
sodium phosphate
What law predicts the expansion of a balloon when helium is added?
,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)
463 mol
At what temperature is a liquid converted into a gas?
the boiling point of the liquid
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?
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)
21.3 g
Two molecules of ethane experience what type of attractive forces?
London forces
A solution contains the label 0.2 M KNO3. What is the correct interpretation of this concentration?
There are 0.2 moles of KNO3 in 1 L of solution.
Which properly represents the Lewis structure of hydrogen sulfide, H2S?
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]
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?
30.0 tablets
What term is used to describe atoms of the same element that have different masses?
isotopes
Classify the following reaction: H2SO4(aq) + 2KOH(aq) → K2SO4(aq) + 2H2O(aq)
, acid - base
Which of the following statements correctly describes Charles's Law?
The volume of a gas is directly proportional to the Kelvin temperature of the gas, if the pressure and
amount of gas remain constant.
Which statement concerning the elements fluorine, chlorine, bromine, and iodine is FALSE?
They all have the same electron configuration.
Choose the best classification of the reaction represented by the following equation: MgO(s) + CO2(g)
→ MgCO3(s)
combination
In what region on the periodic table are elements with the lowest electronegativity values found?
bottom left corner
The modern periodic law states that the physical and chemical properties of the elements are periodic
functions of what property?
atomic number
Tungsten is a metal containing 74 protons, and is used widely in the electronics industry. What is the
chemical symbol for tungsten?
W
What kind of bonding exists in substances that consist of discrete molecules?
covalent
What is the mass of 4.35 moles of aluminum?
117 g
Emergency treatment of cardiac arrest victims sometimes involves injection of a calcium chloride
(CaCl2) solution directly into the heart muscle. Which statement about the compound CaCl2 is FALSE?
The anion in this compound is Cl2−.
What is the mass of 3.01 mol of sulfur atoms?
96.5 g
What is the mass of a 0.150 mole sample of sulfur?
4.81g
What are the three primary particles found in an atom?
electron, neutron, and proton
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]
1.30 g
What is the number 3,000 written in scientific notation using the proper number of significant figures?
3 × 10^3
Which statement about the modern periodic table is FALSE?
Elements in the same period share similar chemical and physical properties.
Which of the following is NOT a unit for measuring pressure?
kJ
A covalent bond involves which of the following?
sharing of electrons between two atoms
Which statement correctly describes what is happening in the reaction shown below?
2Mg(s) + S2(g) → MgS(s)
Mg is oxidized.
Which statement explains why isotopes have different mass numbers?
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?
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)
16
When a neutral atom gains one or more electrons, what type of particle is formed?
an anion
What is the name of the ionic compound with the formula Na3PO4?
sodium phosphate
What law predicts the expansion of a balloon when helium is added?
,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)
463 mol
At what temperature is a liquid converted into a gas?
the boiling point of the liquid
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?
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)
21.3 g
Two molecules of ethane experience what type of attractive forces?
London forces
A solution contains the label 0.2 M KNO3. What is the correct interpretation of this concentration?
There are 0.2 moles of KNO3 in 1 L of solution.
Which properly represents the Lewis structure of hydrogen sulfide, H2S?
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]
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?
30.0 tablets
What term is used to describe atoms of the same element that have different masses?
isotopes
Classify the following reaction: H2SO4(aq) + 2KOH(aq) → K2SO4(aq) + 2H2O(aq)
, acid - base
Which of the following statements correctly describes Charles's Law?
The volume of a gas is directly proportional to the Kelvin temperature of the gas, if the pressure and
amount of gas remain constant.
Which statement concerning the elements fluorine, chlorine, bromine, and iodine is FALSE?
They all have the same electron configuration.
Choose the best classification of the reaction represented by the following equation: MgO(s) + CO2(g)
→ MgCO3(s)
combination
In what region on the periodic table are elements with the lowest electronegativity values found?
bottom left corner
The modern periodic law states that the physical and chemical properties of the elements are periodic
functions of what property?
atomic number
Tungsten is a metal containing 74 protons, and is used widely in the electronics industry. What is the
chemical symbol for tungsten?
W
What kind of bonding exists in substances that consist of discrete molecules?
covalent
What is the mass of 4.35 moles of aluminum?
117 g
Emergency treatment of cardiac arrest victims sometimes involves injection of a calcium chloride
(CaCl2) solution directly into the heart muscle. Which statement about the compound CaCl2 is FALSE?
The anion in this compound is Cl2−.
What is the mass of 3.01 mol of sulfur atoms?
96.5 g
What is the mass of a 0.150 mole sample of sulfur?
4.81g
What are the three primary particles found in an atom?
electron, neutron, and proton
