Download Bellin College Homework Supplement

Bellin College
CH 125 2016
Homework
Supplement
1
Chapter 1 – Homework
1. How can the study of chemistry help you in your desired profession?
Limit answer to 1-2 paragraphs. Write clearly and legibly. There is no
right or wrong answer. You are simply stating your opinion.
2. A
good definition of chemistry is:
A) The science that seeks to understand what matter does by studying what atoms
and molecules do.
B) The science that seeks to understand what living organisms do by studying the
molecules that make up the organism.
C) The science that seeks to understand what the universe does by studying
interactions of molecules with atoms.
D) The science that seeks to understand the interactions of molecules for the sake of
advancing human control over nature.
E) None of the above
Answer:
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3. Which statement about the scientific method is TRUE?
A) The scientific method emphasizes reason as the way to understand the world.
B) The scientific method emphasizes observation and reason as the way to
understand the world.
C) The scientific method emphasizes observation and experimentation as the way to
understand the world.
D) The scientific method emphasizes scientific laws as the way to understand the
world.
E) All of the above statements are false.
Answer:
4. Which of the statements below is NOT part of the scientific method?
A) Observation and measurement
B) Formation of a hypothesis
C) Testing of a hypothesis by experimentation
D) Refinement of a hypothesis as needed
E) All of the above steps are part of the scientific method
Answer:
5. Which statement about a hypothesis is TRUE?
A) It is a tentative interpretation or explanation.
B) It has the potential to be proven wrong.
C) It can be tested by experiments.
D) It is part of the scientific method.
E) All of the above statements are true.
Answer:
6. Which of the following is an example of an observation?
A) All matter is composed of small, indestructible particles called atoms.
B) Reactions occur due to the transfer of electrons.
C) When a can of soda pop is opened, a fizzing sound is heard.
D) Flammable objects contain phlogiston.
E) None of the above
Answer:
7. Which statement accurately describes the purpose of experiments?
A) Experiments are designed to produce the results predicted by a theory.
B) Experiments can be replaced by a simple, logical reasoning of known facts.
C) Experiments are designed to produce unexplainable results for further
investigation.
D) Experiments look for other observable predictions of a theory.
E) None of the above
Answer:
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8.Which of the following is considered a hypothesis (as opposed to an observation)?
A) Spiders have eight legs.
B) Birds can fly because they have hollow bones.
C) Fresh lava from a volcano is hot.
D) The Washington Monument is 555 feet tall.
E) None of the above
Answer:
9.The key to success in chemistry is:
A) Curiosity.
B) Mathematical skills.
C) Commitment.
D) Practice.
E) All of the above
Answer:
10. In the forensic laboratory, a bullet (mass 15.1g) found at a crime scene
may be used as evidence in a trial if the percentage of three metals, usually
lead, tin, and antimony, is a match to the composition of metals in a bullet
from the suspect’s ammunition. If a bullet found at the crime scene contains
13.9 g of lead, 0.3 g of tin, and 0.9 g of antimony, what is the percentage of each
metal in the bullet? Express your answers to the ones place.
MUST SHOW WORK FOR FULL CREDIT!!
4
11. A bullet (also mass 15.1g) seized from the suspect’s ammunition has a
composition of lead 11.6 g, tin 0.5 g, and antimony 0.4 g.
a.
What is the percentage of each metal in the bullet? Express your
answers to the ones place.
b.
Could the bullet removed from the suspect’s ammunition be considered
as evidence that the suspect was at the crime scene?
12. Solve the following equation for m:
heat = m × ΔT × SH
13.
a. Using the graph shown ( plot of child’s Temp versus Time)
what is the child’s temperature 15 min after Tylenol was given?
b. How many minutes elapsed before the temperature
decreased to 38.0 °C?
5
Chapter 2 - Homework
14. Round off each of the following numbers to three significant figures:
a. 35.7823 m
b. 0.002 621 7 L
c. 3.8268 × 103 g
15. Perform the following calculations of measured numbers. Round off the
calculator display or add zeros to give each answer with the correct number of
significant figures.
a.
56.8 × 0.37 =
b.
c.
=
=
16.Perform the following calculations and round off the calculator display or
add zeros to give each answer with the correct number of decimal places:
1.
104.45 mL + 0.838 mL + 46 mL =
2.
153.247 g − 14.82 g =
17. Levsin (hyoscyamine), used to treat stomach and bladder problems, is
available as drops with 0.125 mg Levsin per 1 mL of solution. Write the
equality and its corresponding conversion factors, and identify each number
as exact or give the number of significant figures.
18. Greg’s doctor has ordered a PET scan of his heart. In radiological imaging
such as PET or CT scans, dosages of pharmaceuticals are based on body mass.
If Greg weighs 144 lb, what is his body mass in kilograms?
6
19. A doctor’s order for 0.50 g of Keflex is available as 250-mg tablets. How
many tablets of Keflex are needed? In the following setup, fill in the missing
parts of the conversion factors, show the canceled units, and give the correct
answer:
20. A person who exercises regularly has 16% body fat by mass. If this person
weighs 155 lb, what is the mass, in kilograms, of body fat?
21. Uncooked lean ground beef can contain up to 22% fat by mass. How many
grams of fat would be contained in 0.25 lb of the ground beef?
22. Ken, a 195-lb male patient, has a blood volume of 7.5 qt. If the density of
blood is 1.06 g/mL, what is the mass, in grams, of Ken’s blood?
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Chapter 3 – Homework
23.Classify each of the following as a pure substance (element or compound)
or a mixture (homogeneous or heterogeneous):
a. copper in copper wire
b. a chocolate-chip cookie
c. nitrox, a combination of oxygen and nitrogen used to fill scuba tanks
24. Classify each of the following as a physical or chemical change:
a. A gold ingot is hammered to form gold leaf.
b. Gasoline burns in air.
c. Garlic is chopped into small pieces
25.The typical temperature in a hospital room is set at 21 °C. What is that
temperature in degrees Fahrenheit? ( show work for full credit!)
26.In a type of cancer treatment called thermotherapy, temperatures as high
as 113 °F are used to destroy cancer cells or make them more sensitive to
radiation. What is that temperature in degrees Celsius? ( show work for full
credit!)
27.A child has a temperature of 103.6 °F. What is this temperature on a Celsius
thermometer? ( show work for full credit!). How would you treat this child?
28.A defibrillator gives a high-energy-shock output of 360 J. What is this
quantity of energy in calories?
8
29.The Nutrition Facts label for crackers states that 1 serving contains 19 g of
carbohydrate, 4 g of fat, and 2 g of protein. What is the energy from each food
type and the total energy, in kilocalories, for one serving of crackers?
Round off the kilocalories for each food type to the tens place.
30.During surgery or when a patient has suffered a cardiac arrest or stroke,
lowering the body temperature will reduce the amount of oxygen needed by
the body. Some methods used to lower body temperature include cooled
saline solution, cool water blankets, or cooling caps worn on the head. How
many kilojoules are lost when the body temperature of a surgery patient with
a blood volume of 5500 mL is cooled from 38.5 °C to 33.2 °C? (Assume that the
specific heat and density of blood is the same as for water.)
31.Ice bag therapy is used by sports trainers to treat muscle injuries.
If 260. g of ice are placed in an ice bag, how much heat, in joules, will be
absorbed to melt all the ice at 0 °C?
9
32.In a sauna, 122 g of water is converted to steam at 100 °C. How many
kilojoules of heat are needed?
33.Charles has increased his activity by doing more exercise. After a session of
using small weights, he has a sore arm. An ice bag is filled with 125 g of ice at
0.0 °C. The heat of fusion for ice is 334 J/g. How much heat, in kilojoules, is
absorbed to melt the ice, and to raise the temperature of the water to body
temperature, 37.0 °C?
34.How many kilojoules are released when 75.0 g of steam at 100 °C
condenses, cools to 0 °C, and freezes at 0 °C? (Hint: The solution will require
three energy calculations.)
10
Chapter 4 – Homework
35. Zinc, a micro-mineral, is needed for metabolic reactions in cells, DNA
synthesis, the growth of bones, teeth, and connective tissue, and the proper
functioning of the immune system. For an atom of zinc that has a mass number
of 68, determine the following:
a. the number of protons
b. the number of neutrons
c. the number of electrons
36. Chromium, a micro-mineral needed for maintenance of blood sugar levels,
has four naturally occurring isotopes:
a.
b.
c.
d.
Determine the number of protons and number of neutrons in each of these
isotopes.
37.There are two naturally occurring isotopes of boron. The isotope 105 B has
a mass of 10.01 amu with an abundance of 19.80%, and the isotope 115 B has
a mass of 11.01 amu with an abundance of 80.20%. Calculate the atomic mass
for boron using the weighted average mass method.
38.Nitrogen is an element that is used in the formation of amino acids,
proteins, and nucleic acids. Draw the orbital diagram for nitrogen. (Use the
box diagrams). Also write its Abbreviated Electron Configuration.
11
39.Silicon is a micro-mineral needed for the growth of bones, tendons, and
ligaments. Draw or write each of the following for silicon:
a. orbital diagram
b. abbreviated orbital diagram
c. electron configuration
d. abbreviated electron configuration
40. Write the complete and abbreviated electron configurations for sulfur,
which is a macro-mineral in proteins, vitamin B1, and insulin.
41.Using the periodic table, write the group number, the period, and the
valence electron configuration for the following:
a. calcium
b. iodine
c. Lead
42. Draw the Lewis symbol for each of the following:
a. bromine
b. aluminum
43. Identify the smaller atom in each of the following pairs:
a. N or F
b. K or Kr
c. Ca and Sr
43. Indicate the element in each group that has the higher ionization energy
and explain your choice.
a. K or Na
b. Mg or Cl
c. F, N, or C
12
Chapter 5 – Homework
43. Identify and write the symbol for each of the following types of radiation:
a. Contains two protons and two neutrons
b. Has a mass number of 0 and a 1– charge
44. Smoke detectors that are used in homes and apartments contain
americium-241, which undergoes alpha decay. When alpha particles collide
with air molecules, charged particles are produced that generate an electrical
current. If smoke particles enter the detector, they interfere with the
formation of charged particles in the air, and the electrical current is
interrupted. This causes the alarm to sound and warns the occupants of the
danger of fire. Write the balanced nuclear equation for the decay of
americium-241.
45. Predict the products of the following nuclear reactions.
a.
239
Pu
b.
235
92
U  23190Th
c.
1
1
H
d.
6
3
Li + 10 n
e.
27
13
f.
9
4
Al +

4
2
He
+
+
_______
_______
+ 31 H  _______
4
2
He
Be + 11 H

4
2
He
+
_______

30
15
P
+
_______

4
2
He
+
_______
13
g.
37
19
K 
h. _______ +
i.
238
92
U
0
+1
1
0
e
n
+ 42 He 
+
_______

142
56
1
0
+
n
Ba
+
91
36
Kr
+
3 10 n
_______
46. What is the composition of the nucleus of the following isotopes?
Isotope
Protons
Neutrons
64Ni
28
136I
53
195Au
79
47.If you are given a 2,900-gram sample of Hydrogen, and Hydrogen has a
half-life of 2,450 years. Calculate the following:
A. How much hydrogen is left after 19,600 years?
B. How many half-lives must occur to reach 5.66 grams of hydrogen?
C. How many half-lives must occur to reach 45.31 grams?
D. How many years have passed for B? How many years have passed for C?
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48. I-131 has a half- life of 8 days. If a Hospital received a shipment of 200g of
I-131. How much of it will remain after 32 days?
49. Tc-99m has a half -life of 6 hours. If a Hospital received a shipment of 200g
of Tc-99m. How much of it will remain after 24 hours?
50. The half-life of U-232 is 70 years. How many half- lives will it take for a 10g
sample of U-232 to be reduced to 1.25g?
51. Carbon material in the bones of humans and animals assimilates carbon
until death. Using radiocarbon dating, the number of half-lives of carbon-14
from a bone sample determines the age of the bone. Suppose a sample is
obtained from a prehistoric animal and used for radiocarbon dating. We can
calculate the age of the bone or the years elapsed since the animal died by
using the half-life of carbon-14, which is 5730 yr. If the sample shows that four
half-lives have passed, how much time has elapsed since the animal died?
15
Chapter 6 – Homework
52. Write the symbol and name for the ion that has
a. 7 protons and 10 electrons.
b. 20 protons and 18 electrons.
53. Consider the elements aluminum and oxygen.
a. Identify each as a metal or a nonmetal.
b. State the number of valence electrons for each.
c. State the number of electrons that must be lost or gained for each to achieve
an octet.
d. Write the symbol, including its ionic charge, and name for each resulting
ion.
54. Antifouling paint contains Cu2O, which prevents the growth of barnacles
and algae on the bottoms of boats. What is the name of Cu2O?
55.An antacid called Amphojel contains aluminum hydroxide, which treats
acid indigestion and heartburn. Write the formula for aluminum hydroxide.
56.Write the formula for a compound containing ammonium ions and
phosphate ions.
57.Name the following ionic compounds:
a.
Cu(NO2)2
b.
KClO3
16
58. Write the names for each of the following molecular compounds:
a. SiBr4
b. Br2O
59.Identify each of the following compounds as ionic or molecular and give its
name:
a. K3P
b. NiSO4
c. SO3
60. Draw the Lewis structure for PCl3, phosphorus tri-chloride, used
commercially to prepare insecticides and flame -retardants.
61. Sodium chlorite, NaClO2, is a component of mouthwashes, toothpastes, and
contact lens cleaning solutions. Draw the Lewis structure for the chlorite ion,
ClO2–.
62. Draw the Lewis structure for the polyatomic ion NH2–.
63. Using electronegativity values, classify each of the following bonds as
nonpolar covalent, polar covalent, or ionic:
O—K
N—N
Cl—As
P—Br
17
64. Use VSEPR theory to predict the shape of the polyatomic ion NO3–.
65. Predict the shape of a molecule of SiCl4
66. Indicate the major type of molecular interaction—dipole–dipole
attractions, hydrogen bonding, or dispersion forces—expected of each of the
following:
a. HF
b. Br2
c. PCl3
67.Would a PCl3 molecule be polar or nonpolar? Justify your answer.
18
Chapter 7 – Homework
68.Indicate the number of each type of atom in the following balanced
chemical equation:
Fe2S3(s) + 6HCl(aq) → 2FeCl3(aq) + 3H2S(g)
69. Balance the following equations;
1. ___N2 +
___H2

___NH3
2. ___KClO3

___KCl
+
___O2
3. ___NaCl
+
___F2 
___NaF
4. ___H2
+
___O2

___H2O
5. ___AgNO3
+
___MgCl2

___AgCl
+
___Mg(NO3)2
6. ___AlBr3
+
___K2SO4

___KBr
+
___Al2(SO4)3
7. ___CH4
+
___O2

___CO2
+
___H2O
+
___Cl2
70. Write Balanced Equations for the following and classify each as
Combination, Decomposition, Single Replacement, Double Replacement, or
Combustion.
A) Solid Copper reacts with an aqueous solution of Silver Nitrate (AgNO3) forming Solid
Silver (Ag) and Copper II Nitrate Cu(NO3)2 solution.
B) Methane gas (CH4) reacts with Oxygen gas (O2) producing Carbon Dioxide gas and Water
gas.
19
C) Solid Calcium Nitrate (Ca(NO3)2) decomposes forming solid calcium oxide (CaO) and
Nitrogen Dioxide gas (NO2)
D) Sodium Chloride Solution (NaCl) reacts with Silver Nitrate solution (AgNO3) producing
solid Silver Chloride (AgCl) and Sodium Nitrate solution (NaNO3).
E) Aqueous Acetic Acid (CH3COOH) neutralizes Sodium Hydroxide (NaOH) solution yields
Aqueous Sodium Acetate (NaCH3COO) and liquid water.
F) Sulfuric Acid gas (H2SO4) reacts with Ammonia gas (NH3) forming ammonium Sulfate
solid {(NH4)2SO4}
71. Solve the following:
A) An extra strength aspirin tablet contains 500. mg of aspirin (C9H8O4). How many
molecules of aspirin are in one extra strength tablet? How many carbon atoms are
there in one tablet?
B) A block of salt contains 3.45 x 1026 formula units of NaCl. How many grams is
this?
20
C) A sample of barium nitrate {Ba(NO3)2}contains 6.80 x 1024 formula units. How
many grams is this?
D) How many formula units of sodium hydrogen carbonate (NaHCO3) are in
1.8 g?
E) If you burned 4.0 x 1024 molecules of natural gas, or methane (CH4), during a
laboratory experiment, what mass of methane did you burn?
F) How many hydrogen atoms are in 3.5 g of NaOH? Oxygen atoms?
G) A bottle contains 100.0 g of sodium nitrate (NaNO3). How many oxygen atoms are
in this bottle?
H) Find the number of oxygen atoms in 605 g of diphosphorous pentoxide
21
72. Solve the following:
Remember to balance all equations!!!
(i) How many moles of hydrochloric acid are required to completely dissolve 2.6 moles
of magnesium hydroxide? Mg(OH)2 (s) + HCl (aq) MgCl2 (aq) +H2O (l)
(ii) How many moles of ammonium acetate (NH4CH3COO) are produced when
moles of acetic acid (CH3COOH) react completely with an excess of ammonium
hydroxide?
NH4OH (aq) + CH3COOH (aq) NH4CH3COO (aq) +H2O (l)
9.2
(iii) How many moles of O2 are required to burn 1 mol of C3H8 (propane) molecules in a
camping stove? (This is a combustion reaction).
(iii) “Slaked lime,” Ca(OH) 2, is formed from “quick-lime” (CaO) by adding water. What mass
of water is needed to convert 10 g of quicklime to slaked lime? What mass of slaked lime is
produced? CaO(s) + H2O(l)  Ca(OH)2 (s)
(iv) Camels store the fat tristearin (C57H110O6) in the hump. As well as being a source of
energy, the fat is a source of water, because when it is used the following reaction takes
place. What mass of water is available from 1234.0 g of fat?
2 C57H110O6(s) + 163 O2(g)  114 CO2(g) + 110 H2O(l)
22
73. Consider the following reaction:
I2O5 (g) + 5 CO (g)  5 CO2 (g) + I2 (g)
a. If 80.0 grams of iodine (V) oxide, I2O5, reacts with 28.0 grams of carbon
monoxide, CO, determine the mass of iodine I2, which could be produced?
b. If, in the above situation, only 0.160 moles, of iodine, I2 was produced
i. what mass of iodine was produced?
ii. what was the percentage yield of iodine?
74. How much heat energy will be released when 6.44g S reacts with excess O2
according to the following equation: 2S(s) + 3O2(g) 2SO3(g) ΔH = - 791.4kJ
75. How much heat energy will be absorbed when 38.2 g Bromine reacts with
excess Hydrogen according to the following reaction:
H2(g) + Br2(g) 2HBr(g) ΔH = + 72.80kJ
23
Chapter 8 – Homework
76. Identify the property of a gas that is described by each of the following:
a. Increase the kinetic energy of gas particles
b. The force of the gas particles hitting the walls of the container
c. The space that is occupied by a gas
77. The oxygen in a tank in the hospital respiratory unit has a pressure of
4820 mmHg. Calculate the pressure, in atmospheres, and also in kPa of the
oxygen gas:
atmospheres:
kPa (Kilopascals):
78. In an underground natural gas reserve, a bubble of methane gas, CH4, has a
volume of 45.0 mL at 1.60 atm. What volume, in milliliters, will the gas bubble
occupy when it reaches the surface where the atmospheric pressure is
744 mmHg, if there is no change in the temperature or amount of gas?
79. Helium gas is used to inflate the abdomen during laparoscopic surgery. A
sample of helium gas has a volume of 5.40 L and a temperature of 15 °C. What
is the final volume, in liters, of the gas if the temperature has been increased
to 42 °C at constant pressure and amount of gas?
24
80. Home oxygen tanks, which provide an oxygen-rich environment, can be
dangerous if they are heated, because they can explode. Suppose an oxygen
tank has a pressure of 120 atm at a room temperature of 25 °C. If a fire in the
room causes the temperature of the gas inside the oxygen tank to reach
402 °C, what will be its pressure in atmospheres? The oxygen tank may
rupture if the pressure inside exceeds 180 atm. Would you expect it to
rupture?
81. In a storage area of a hospital where the temperature has reached 55 °C,
the pressure of oxygen gas in a 15.0-L steel cylinder is 965 Torr. To what
temperature, in degrees Celsius, would the gas have to be cooled to reduce the
pressure to 850. Torr when the volume and amount of the gas do not change?
82. A 25.0-mL bubble is released from a diver’s air tank at a pressure of
4.00 atm and a temperature of 11 °C. What is the volume, in milliliters, of the
bubble when it reaches the ocean surface, where the pressure is 1.00 atm and
the temperature is 18 °C? (Assume the amount of gas in the bubble does not
change.)
25
83. A sample containing 8.00 g of oxygen gas has a volume of 5.00 L. What is
the final volume, in liters, after 4.00 g of oxygen gas is added to the 8.00 g of
oxygen in the balloon, if the temperature and pressure do not change?
84. How many grams of N2(g) are in 5.6 L of N2(g) at STP?
85. Dinitrogen oxide, N2O, which is used in dentistry, is an anesthetic also
called laughing gas. What is the pressure, in atmospheres, of 0.350 mole of
N2O at 22 °C in a 5.00-L container?
86. Butane, C4H10, is used as a fuel for camping stoves. If you have 108 mL of
butane gas at 715 mmHg and 25 °C , what is the mass, in grams, of butane?
87. Calcium carbonate, CaCO3, in antacids reacts with HCl in the stomach to
reduce acid reflux. How many liters of CO2 are produced at 752 mmHg and
24 °C from a 25.0-g sample of calcium carbonate?
CaCO3(s) +2HCl(aq)  CaCl2(aq) + H2O(l) + CO2(g)
26
Chapter 9 – Homework
88. Indicate whether solutions of each of the following contain only ions, only
molecules, or mostly molecules and a few ions. Write the equation for the
formation of a solution for each of the following:
a.
Na2SO4(s), a strong electrolyte
b.
sucrose, C12H22O11(s), a nonelectrolyte
c.
acetic acid, HC2H3O2(l), a weak electrolyte
89. The laboratory tests for a patient indicate a blood calcium level
of 8.8 mEq/L.
a. How many moles of calcium ion are in 0.50 L of blood?
b. If chloride ion is the only other ion present, what is its
concentration in mEq/L?
90. At 20 °C, the solubility of KCl is 34 g/100 g of H2O. In the laboratory, a
student mixes 75 g of KCl with 200. g of H2O at a temperature of 20 °C.
a. How much of the KCl will dissolve?
b. Is the solution saturated or unsaturated?
c. What is the mass, in grams, of any solid KCl left un-dissolved on the
bottom of the container?
27
91. Predict whether each of the following ionic compounds is soluble in
water and explain why:
a. Na3PO4
b. CaCO3
92. Predict whether a solid might form in each of the following mixtures of
solutions. If so, write the net ionic equation for the reaction.
a. NH4Cl(aq) + Ca(NO3)2(aq) 
b. Pb(NO3)2(aq) + KCl(aq)
93. What is the mass percent of NaOH in a solution prepared by dissolving
30.0 g of NaOH in 120.0 g of H2O
94. What is the volume percent (v/v) of Br2 in a solution prepared by
dissolving 12 mL of liquid bromine (Br2) in the solvent carbon
tetrachloride (CCl4) to make 250 mL of solution?
95. What is the mass/volume percent (m/v) of NaOH in a solution prepared by
dissolving 12 g of NaOH in enough water to make 220 mL of solution?
28
96. What is the molarity of a solution that contains 75.0 g of KNO3 dissolved in
0.350 L of solution?
97. A topical antibiotic is 1.0% (m/v) clindamycin. How many grams of
clindamycin are in 60. mL of the 1.0% (m/v) solution?
98. In 2010, the FDA approved a 2.0% (m/v) morphine oral solution to treat
severe or chronic pain. How many grams of morphine does a patient receive if
0.60 mL of 2.0% (m/v) morphine solution was ordered?
99. How many milliliters of a 6.0 M HCl solution will provide 164 g of HCl?
100. How many grams of zinc can react with 225 mL of a 0.200 M HCl solution?
Zn(s) + 2HCl(aq)  ZnCl2(aq) + H2(g)
29
101. How many milliliters of a 0.330 M Na2SO4 solution are needed to react
with 26.8 mL of a 0.216 M BaCl2 solution?
Na2SO4(aq) + BaCl2(aq) BaSO4(s) + 2NaCl(aq)
102. What initial volume of a 15% (m/v) mannose solution is needed to
prepare 125 mL of a 3.0% (m/v) mannose solution?
103. What is the molarity of a solution when 50.0 mL of a 4.00 M KOH solution
is diluted to 200. mL?
104. Ethylene glycol, C2H6O2, a nonelectrolyte, is added to the water in a
radiator to give a solution containing 0.75 mole of ethylene glycol in
1 kg of water (solvent). What is the boiling point of the solution?
105. Describe each of the following solutions as isotonic, hypotonic, or
hypertonic. Indicate whether a red blood cell placed in each solution will
undergo hemolysis, crenation, or no change.
a. a 5% (m/v) glucose solution
b. a 0.2% (m/v) NaCl solution
30
Chapter 10 – Homework
106. Indicate whether the following changes will increase, decrease, or have
no effect on the rate of reaction:
a. increasing the temperature
b. increasing the number of reacting molecules
c. adding a catalyst
107. Write the equilibrium constant expression for the following reaction’s:
A.
B.
C.
D.
2CH3OH(g) + 3O2(g)
2CO2(g) + 4H2O(g)
107. The decomposition of dinitrogen tetroxide forms nitrogen dioxide.
What is the numerical value of Kc at 100 °C if a reaction mixture at
equilibrium contains 0.45 M N2O4 and 0.31 M NO2?
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108. Calculate the numerical value of Kc if an equilibrium mixture contains
0.040 M NH3, 0.60 M H2, and 0.20 M N2.
109. When the alkene ethene (C2H4) reacts with water vapor, the alcohol
ethanol (C2H5OH) is produced. If an equilibrium mixture contains
0.020 M C2H4 and 0.015 M H2O, what is the equilibrium concentration of
C2H5OH? At 327 °C, the Kc is 9.0 × 103.
110. Methanol, CH3OH, is finding use as a fuel additive. Describe the effect of
each of the following changes on the equilibrium mixture for the following
reaction:
2CH3OH(g) + 3O2(g)
2CO2(g) + 4H2O(g) + 1450 kJ
a. Adding more CO2
b. Adding more O2
c. Increasing the volume of the container
d. Increasing the temperature
e. Adding a catalyst
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Chapter 11 – Homework
111 a. Identify each of the following as an acid or a base and give its name:
1. H3PO4, ingredient in soft drinks
2. NaOH, ingredient in oven cleaner
b. Write the formula for each of the following:
1. magnesium hydroxide, ingredient in antacids
2. hydrobromic acid, used industrially to prepare bromide compounds
112. In each of the following equations, identify the reactant that is a
Brønsted–Lowry acid and the reactant that is a Brønsted–Lowry base:
a
HBr(aq) + H2O(l)  H3O+(aq) + Br–(aq)
b.
CN–(aq) + H2O(l)
HCN(aq) + OH–)(aq)
113. Determine the Bronsted-Lowry acid-base pairs for the following
reactions:
a. HSO3- (aq) +H2O(l) SO32- (aq) + H3O+ (aq)
b. HNO3 (aq) + H2O (l)  NO3- (aq) + H3O+ (aq)
c. HC4H7O2 (aq) + H2O(l) C4H7O2- (aq) + H3O+ (aq)
d. HSO3- (aq) + H2O (l)  H2SO3 (aq) + OH- (aq)
e. NH3 (aq) + H2O (l)  NH4+ (aq) + OH- (aq)
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114. Identify the acid, base, conjugate acid and conjugate bases in the
following examples:
a. H2S (aq) + H2O(l) HS- (aq) +H3O+ (aq)
b. HClO2 (aq) + H2O (l) ClO2- (aq) + H3O+ (aq)
c. H2O (l) + NH3 (aq)  NH4+ (aq) + OH- (aq)
d. CO22- (aq) + H2O (l) HCO3- (aq) + OH-(aq)
e. H2PO4- (aq) +H2O (l) H3PO4 (aq) + OH- (aq)
115. Does the equilibrium mixture’s of the following reaction’s contain mostly
reactants or products?
a. H2S (aq) + H2O(l)
b. HClO2 (aq) + H2O (l)
HS- (aq)
+H3O+ (aq)
ClO2- (aq) + H3O+ (aq)
c. H2O (l) + NH3 (aq)
NH4+ (aq) + OH- (aq)
d. CO22- (aq) + H2O (l)
HCO3- (aq) + OH-(aq)
e. H2PO4- (aq) +H2O (l)
H3PO4 (aq) + OH- (aq)
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116. Write the acid dissociation constant expression for the weak acid’s:
A. Nitrous acid
B. Ammonium ion
C. Acetic acid
D. Sulfurous acid
117. A vinegar solution has a [OH–] = 5.0 × 10–12 M at 25°C. What is the [H3O+]
of the vinegar solution? Is the solution acidic, basic, or neutral?
118. What is the [H3O+] of an ammonia cleaning solution with
[OH–] = 4.0 × 10–4 M? Is the solution acidic, basic, or neutral?
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119. Consider the pH of the following body fluids:
a. Place the pH values of the body fluids on the list in order of most
acidic to most basic.
c. Which body fluid has the highest [H3O+]?
120. What is the pH of bleach with [H3O+] = 4.2 × 10–12 M?
121. What is the pH of an ammonia solution with [OH–] = 3.7 × 10–3 M?
122. Calculate the pH of a sample of bile that has [OH–] = 1.3 × 10–6 M.
123. What are the [H3O+] and [OH–] of Diet Coke that has a pH of 3.17?
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124. If 16.3 mL of a 0.185 M Sr(OH)2 solution is used to titrate the HCl in a
25.0-mL sample of gastric juice, what is the molarity of the HCl solution?
125. One of the conjugate acid–base pairs that buffers the blood plasma is
H2PO4– /HPO42–, which has a Ka of 6.2 × 10–8. What is the pH of a buffer that is
prepared from 0.20 M H2PO4– and 1.00 M HPO42–?
126. What is the pH of a buffer made from 0.10 M formic acid (HCHO2)
and 0.010 M formate (CHO2–)?
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