CBL Laboratory Manual

Student Edition
 A Glencoe Program

Hands-On Learning: Teacher Resources:

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CBL Laboratory Manual, SE/TE Spanish Resources
Small-Scale Laboratory Manual, SE/TE Section Focus Transparencies and Masters
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Review/Reinforcement: Solutions Manual
Study Guide for Content Mastery, SE/TE
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Windows/MacIntosh
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Supplemental Problems

Assessment:
Chapter Assessment
MindJogger Videoquizzes (VHS/DVD)
Computer Test Bank, Windows/MacIntosh

Copyright © by The McGraw-Hill Companies, Inc.

All rights reserved. Permission is granted to reproduce the material contained herein
on the condition that such material be reproduced only for classroom use; be provided
to students, teachers, and families without charge; and be used solely in conjunction
with the Chemistry: Matter and Change program. Any other reproduction, for use or
sale, is prohibited without prior written permission of the publisher.

Send all inquiries to:

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ISBN 0-07-824530-3
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 CBL LABORATORY MANUAL

Contents
To the Student . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
Organization of Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv
Sending Data to Graphical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . v
CBL Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v
Safety in the Laboratory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi
Safety Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii

Laboratory Activities
1 Quantitative and Qualitative Observations . . . . . . . . . . . . . . . . . 1
2 Conductivity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3 Melting and Freezing Points . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4 Boyle’s Law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5 Gay-Lussac’s Law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6 Determining Molar Mass Using Freezing Point Depression . . . 21
7 Calorimetry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
8 Hess’s Law . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
9 Determine the Molar Mass of an Unknown Acid . . . . . . . . . . . 33
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

10 Reaction Potentials of Metals . . . . . . . . . . . . . . . . . . . . . . . . . 37

CBL Laboratory Manual Chemistry: Matter and Change iii

 To the Student
Chemistry is the science of matter, its properties, and changes. In your classroom
work in chemistry, you will learn a great deal about the information that has been
gathered by scientists about matter. But, chemistry is not just information. It is
also a process for finding out more about matter and its changes. Laboratory
activities are the primary means that chemists use to learn more about matter.
The activities in the CBL Laboratory Manual require that you form and test
hypotheses, measure and record data and observations, analyze those data, and
draw conclusions based on those data and your knowledge of chemistry. These
processes are the same as those used by professional chemists and all other
scientists.
CBL (computer-based laboratory) activities use graphing calculators to collect
and analyze real-world data using different probes or sensors. The CBL system is
an interface that collects data from the probes and sends the information to the
calculator. The calculator, in turn, runs stored data collection and processing
programs, which interpret and plot data obtained from the CBL system.

Organization of Activities
• Introduction Following the title and number of each activity, an introduction
provides a background discussion about the problem you will study in the activity.
• Problem The problem to be studied in this activity is clearly stated.
• Objectives The objectives are statements of what you should accomplish by doing
the investigation. Recheck this list when you have finished the activity.
• Materials The materials list shows the apparatus you need to have on hand for the
activity.
• Safety Precautions Safety symbols and statements warn you of potential hazards
in the laboratory. Before beginning any activity, refer to page vii to see what these

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

symbols mean.
• Pre-Lab The questions in this section check your knowledge of important
concepts needed to complete the activity successfully.
• Procedure The numbered steps of the procedure tell you how to carry out the
activity and sometimes offer hints to help you be successful in the laboratory.
Some activities have CAUTION statements in the procedure to alert you to
hazardous substances or techniques.
• Hypothesis This section provides an opportunity for you to write down a hypoth-
esis for this activity.
• Data and Observations This section presents a suggested table or form for
collecting your laboratory data. Always record data and observations in an organ-
ized way as you do the activity.
• Analyze and Conclude The Analyze and Conclude section shows you how to
perform the calculations necessary for you to analyze your data and reach conclu-
sions. It provides questions to aid you in interpreting data and observations in
order to reach an experimental result. You are also asked to form a scientific
conclusion based on what you actually observed, not what “should have
happened.” An opportunity to analyze possible errors in the activity is also given.
• Real-World Chemistry The questions in this section ask you to apply what you
have learned in the activity to other real-life situations. You may be asked to make
additional conclusions or research a question related to the activity.

iv Chemistry: Matter and Change CBL Laboratory Manual

 CBL LABORATORY MANUAL

Sending Data to Graphical Analysis

If using the TI-83 graphing calculator:
1. On the TI calculator, press 2nd Link, then select 4:List… from the SEND menu.
2. Use the down arrow to locate the lists on the SELECT menu. Position the arrow in front
of a list you want to send to GRAPHICAL ANALYSIS and press ENTER to select that
particular list. More than one list may be selected in this manner. A filled box will appear
beside each list that will be sent. To deselect, press ENTER. The filled-in box will
disappear.
3. Press the right arrow on the calculator, then select 1:TRANSMIT. The lists will appear in
columns in the data table window of GRAPHICAL ANALYSIS. They will be labeled with
simple list names from the calculator. If you want to rename the lists or add units, double-
click on the column heading and enter a new name or label in the dialog box.

If using another type of TI graphing calculator with a PC computer:

1. Connect the TI-graph link cable to a free serial port of the Windows computer and to the
port on the bottom edge of the TI calculator.
2. With GRAPHICAL ANALYSIS running, choose Import from the TI Calculator under the
FILE MENU. If the TI-graph link cable is not connected to the serial port designated in
the status box, click on SELECT PORT and choose the correct port for the TI-graph link
cable.

CBL Equipment
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

This diagram shows the basic equipment used in most of these CBL activities. Such
equipment includes the CBL unit, a graphing calculator, link cable, AC adapter for the
CBL unit, DIN adapter (needed for some probes), and a probe or sensor.

DIN adapter
CBL
TI-83 calculator unit

Gas pressure
sensor

Syringe

AC adapter

Link cable

CBL Laboratory Manual Chemistry: Matter and Change v

 CBL LABORATORY MANUAL

Safety in the Laboratory

The chemistry laboratory is a place to experiment and learn. You must assume responsibility
for your own personal safety and that of people working near you. Accidents are usually
caused by carelessness, but you can help prevent them by closely following the instructions
printed in this manual and those given to you by your teacher. The following are some safety
rules to help guide you in protecting yourself and others from injury in a laboratory.

1. The chemistry laboratory is a place for serious Take only small amounts. It is easier to get more
work. Do not perform activities without your than to dispose of excess.
teacher’s permission. Never work alone in the lab- 13. Do not insert droppers into reagent bottles. Pour a
oratory. Work only when your teacher is present. small amount of the chemical into a beaker.
2. Study your lab activity before you come to the lab. 14. Never taste any chemical substance. Never draw
If you are in doubt about any procedures, ask your any chemicals into a pipette with your mouth.
teacher for help. Eating, drinking, chewing gum, and smoking are
3. Safety goggles and a laboratory apron must be prohibited in the laboratory.
worn whenever you work in the lab. Gloves should 15. If chemicals come into contact with your eyes or
be worn whenever you use chemicals that cause skin, flush the area immediately with large quanti-
irritations or can be absorbed through the skin. ties of water. Immediately inform your teacher of
4. Contact lenses should not be worn in the lab, even the nature of the spill.
if goggles are worn. Lenses can absorb vapors and 16. Keep combustible materials away from open
are difficult to remove in an emergency. flames. (Alcohol and acetone are combustible.)
5. Long hair should be tied back to reduce the 17. Handle toxic and combustible gases only under the
possibility of it catching fire. direction of your teacher. Use the fume hood when
6. Avoid wearing dangling jewelry or loose, draping such materials are present.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

clothing. The loose clothing may catch fire and 18. When heating a substance in a test tube, be careful
either the clothing or jewelry could catch on not to point the mouth of the tube at another
chemical apparatus. person or yourself. Never look down the mouth
7. Wear shoes that cover the feet at all times. Bare of a test tube.
feet or sandals are not permitted in the lab. 19. Use caution and the proper equipment when
8. Know the location of the fire extinguisher, safety handling hot apparatus or glassware. Hot glass
shower, eyewash, fire blanket, and first-aid kit. looks the same as cool glass.
Know how to use the safety equipment provided 20. Dispose of broken glass, unused chemicals, and
for you. products of reactions only as directed by your
9. Report any accident, injury, incorrect procedure, or teacher.
damaged equipment immediately to your teacher. 21. Know the correct procedure for preparing acid
10. Handle chemicals carefully. Check the labels of solutions. Always add the acid slowly to the water.
all bottles before removing the contents. Read 22. Keep the balance area clean. Never weigh
the labels three times: before you pick up the chemicals directly on the pan of the balance.
container, when the container is in your hand,
23. Do not heat graduated cylinders, burettes, or
and when you put the bottle back.
pipettes with a laboratory burner.
11. Do not return unused chemicals to reagent bottles.
24. After completing an activity, clean and put away
12. Do not take reagent bottles to your work area your equipment. Clean your work area. Make sure
unless specifically instructed to do so. Use test the gas and water are turned off. Wash your hands
tubes, paper, or beakers to obtain your chemicals. with soap and water before you leave the lab.

vi Chemistry: Matter and Change CBL Laboratory Manual

 CBL LABORATORY MANUAL
The Chemistry: Matter and Change program uses safety symbols to alert you and your students to possible
laboratory dangers. These symbols are provided in the student text in Appendix B and are explained below.
Be sure your students understand each symbol before they begin an activity that displays a symbol.

SAFETY SYMBOLS HAZARD EXAMPLES PRECAUTION REMEDY

Special disposal pro- certain chemicals, Do not dispose of Dispose of wastes as
DISPOSAL cedures need to be living organisms these materials in directed by your
followed. the sink or trash can. teacher.
Organisms or other bacteria, fungi, Avoid skin contact Notify your teacher if
BIOLOGICAL biological materials blood, unpreserved with these materials. you suspect contact
that might be tissues, plant Wear mask or gloves. with material. Wash
harmful to humans materials hands thoroughly.
EXTREME Objects that can boiling liquids, hot Use proper Go to your teacher
burn skin by being plates, dry ice, liquid protection when for first aid.
TEMPERATURE too cold or too hot nitrogen handling.
SHARP Use of tools or razor blades, pins, Practice common- Go to your teacher
glassware that can scalpels, pointed sense behavior and for first aid.
OBJECT easily puncture or tools, dissecting follow guidelines for
slice skin probes, broken glass use of the tool.
Possible danger to ammonia, acetone, Make sure there is Leave foul area and
FUME respiratory tract nail polish remover, good ventilation. notify your teacher
from fumes heated sulfur, moth Never smell fumes immediately.
balls directly. Wear a mask.

Possible danger from improper grounding, Double-check setup Do not attempt to fix
ELECTRICAL electrical shock or liquid spills, short with teacher. Check electrical problems.
burn circuits, exposed condition of wires Notify your teacher
wires and apparatus. immediately.
Substances that can pollen, moth balls, Wear dust mask and Go to your teacher
IRRITANT irritate the skin or steel wool, fiber gloves. Practice extra for first aid.
mucus membranes of glass, potassium care when handling
the respiratory tract permanganate these materials.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

Chemicals that can bleaches such as Wear goggles, Immediately flush

CHEMICAL react with and hydrogen peroxide; gloves, and an the affected area
destroy tissue and acids such as sulfuric apron. with water and
other materials acid, hydrochloric notify your teacher.
acid; bases such as
ammonia, sodium
hydroxide
Substance may be mercury, many metal Follow your teacher’s Always wash hands
TOXIC poisonous if compounds, iodine, instructions. thoroughly after use.
touched, inhaled, or poinsettia plant Go to your teacher
swallowed parts for first aid.

OPEN Open flame may alcohol, kerosene, Tie back hair. Avoid Notify your teacher
ignite flammable potassium wearing loose clothing. immediately. Use fire
FLAME chemicals, loose permanganate, hair, Avoid open flames safety equipment if
clothing, or hair clothing when using flammable applicable.
chemicals. Be aware of
locations of fire safety
equipment.

Eye Safety Clothing Animal Safety Radioactivity

Proper eye Protection This symbol This symbol
protection should be This symbol appears when appears when
worn at all times by appears when safety of animals radioactive
anyone performing substances could and students must materials are used.
or observing science stain or burn be ensured.
activities. clothing.

CBL Laboratory Manual Chemistry: Matter and Change vii

 Name Date Class

LAB 1 CBL LABORATORY MANUAL

Use with
Quantitative and Section 1.3

Qualitative Observations

R eactions are taking place around you all the time. It is important
to be aware of your surroundings and understand how humans
interact with these surroundings. Your five senses allow you to
observe the world in which you live. In the lab, you only use four
senses to make observations. Nothing is ever tasted in the lab.
Sometimes tools can extend your senses. When you describe the
color, odor, or texture of an object, you are making a qualitative
observation. Quantitative observations involve measured quantities,
such as 15 g or 2.5 L. It is important not to confuse observations and
interpretations in the lab. Observations are made using your senses;
interpretations are proposed explanations that are based on
observations. In this lab, you will be making both qualitative and
quantitative observations.

Problem Objectives Materials

How many observations • Measure the change in CBL unit 150-mL beaker
can you make about a temperature related to a TI graphing 100-mL graduated
reaction? Are your chemical reaction. calculator cylinder
observations qualitative • Compare quantitative link cable microspatula
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

or quantitative? observations and qualita- temperature probe glass stirring rod

tive observations. copper(II) chloride paper towel
• Discuss the difference 2  2-in square of magnifying glass
between observations aluminum foil weighing paper
and interpretations.
• Predict one product
produced during the
reaction.

Safety Precautions
• Always wear safety goggles and a lab apron.
• Do not touch chemicals with bare skin.
• Do not inhale vapors that are released.
• Dispose of materials as your teacher instructs.

Pre-Lab
1. What is the difference between observations and 3. What are some tools that scientists use to enhance
interpretations? their observational techniques?
2. Give three examples of qualitative observations
and three examples of quantitative observations.

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 1 1

Name Date Class

LAB 1 CBL LABORATORY MANUAL

Procedure 4. Using the 100-mL graduated cylinder, obtain

50 mL of distilled water. Pour the water into the
Part A: Preparing the CBL System
150-mL beaker.
1. Connect the CBL unit to the temperature probe, 5. Place the temperature probe in the water.
as shown in Figure A. Make sure the tempera- Record an initial temperature of the water by
ture probe is in channel 1. Then, using a link pressing TRIGGER on the CBL unit. Follow
cable, connect the CBL unit to the graphing directions on the calculator to continue
calculator. collecting data.
6. With the temperature probe in the water, trans-
Figure A fer the copper(II) chloride into the water
CBL without touching the probe. Try not to agitate
TI graphing
unit the mixture. Note any temperature change.
calculator Temperature
probe 7. Before stirring the mixture, record as many
observations as possible in Data Table 1.
8. Using the glass stirring rod, stir the mixture.
After stirring, make and record as many obser-
vations as possible.
9. Roll the aluminum foil loosely into a ball. Do
not tightly pack the aluminum. Place the foil
AC adapter ball in the copper(II) chloride mixture. Let the
reaction proceed for about 15 min. Make and
Link cable record as many observations as possible of the
reaction mixture.
10. Record the maximum temperature change that
takes place during the reaction.
2. Turn on the CBL unit and the graphing calcula-

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

11. When the reaction appears to be complete,
tor. Press the PRGM button on the calculator remove the probe from the water. Pour off as
and choose ChemBio from the list of programs. much of the liquid as possible.
Press ENTER on the calculator twice.
12. Label a paper towel with your name and class
3. Choose SET UP PROBES from the MAIN period. Pour the remaining contents onto the
MENU. Enter 1 as the number of probes. paper towel. Set aside the paper towel for
On the SELECT PROBES menu, choose observation on the second day of lab.
TEMPERATURE. Enter 1 as the channel
number.
Cleanup and Disposal
4. From the MAIN MENU, select COLLECT
DATA. On the DATA COLLECTION menu, 1. Disconnect the temperature probe from the
select TRIGGER/PROMPT. CBL unit.
2. After emptying the beaker, clean and rinse the
Part B: Collecting Data beaker. Rinse the probe with distilled water and
1. Obtain a 2  2-in square of aluminum. carefully wipe it dry.
2. Place a small scoop of copper(II) chloride onto 3. Return all equipment to its proper place.
a piece of weighing paper. 4. Clean up the lab area and wash your hands with
3. Make as many observations of the aluminum soap or detergent before leaving the lab.
and the copper(II) chloride as possible. Record
your observations in Data Table 1.

2 Chemistry: Matter and Change • Chapter 1 CBL Laboratory Manual

 Name Date Class

LAB 1 CBL LABORATORY MANUAL

Data and Observations

Data Table 1
Steps Observations

3. Dry copper(II) chloride

Aluminum

5. Initial temperature of water (°C)

7. Copper(II) chloride and water mixture

before stirring

8. Copper(II) chloride and water mixture

after stirring

9. Copper(II) chloride and water mixture

with aluminum

10. Final temperature of mixture (°C)

Analyze and Conclude

1. Observing and Inferring Describe the events that took place that provide evidence for a
chemical reaction.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

2. Observing and Inferring Name one product that is formed in this reaction.

3. Observing and Inferring What observations did you make during this lab? What
interpretations can you make from your observations?

4. Thinking Critically Which of the observations you made were quantitative?

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 1 3

Name Date Class

LAB 1 CBL LABORATORY MANUAL

5. Error Analysis What could be done to improve the accuracy of your measurements in
this activity?

Real-World Chemistry
1. Why is it important for scientists to have 3. How do observation and interpretation skills
as much data as possible before making help when working with the scientific method?
interpretations?
2. Why is important for high school students to
develop their observation skills?

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

4 Chemistry: Matter and Change • Chapter 1 CBL Laboratory Manual

 Name Date Class

LAB 2 CBL LABORATORY MANUAL

Use with
Conductivity Section 8.2

T he solubility of a substance describes the ability of one substance

to dissolve in another substance. Water is used as a solvent to
determine the solubility of various solids. Some substances dissolve in
water; some substances do not.
When dissolved in water, the ions in an ionic compound separate,
or dissociate. As the ions dissociate, electrons are free to move about
in the solution. As these electrons move, it is possible for them to
carry an electric current.
In this activity, the conductivity of substances is used to determine
to what extent substances dissociate in water. This lab compares an
ionic solid to a nonionic substance and relates the effect of
concentration on conductivity.

Problem Objectives Materials

How can an electric current • Predict what substances CBL unit 400-mL beaker
be used to determine the will dissociate in water TI graphing 150-mL beakers (3)
extent to which solid sub- based on their chemical calculator 100-mL graduated
stances dissolve in water? makeup. computer cylinder
• Write balanced equations link cable glass stirring rod
for the dissociation of conductivity probe ring stand with
substances in water. adapter cable test-tube clamp
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

• Compare the conductivity dropper bottles (3) wash bottle of

of various solutions. with: distilled water
• Classify substances as (a) 1M NaCl microspatula
nonionic or ionic. (b) 1M MgCl2 electronic balance
• Determine what effect (c) 1M AlCl3 weighing dishes (2)
concentration has on 50-mL beakers (2) plastic beral
conductivity. with: pipettes (3)
(a) NaCl
(b) sugar
(C12H22O11)

Safety Precautions
• Always wear safety goggles and a lab apron.
• Use caution when working with electricity.
• The conductivity probe is fragile. Use caution when setting this up in
the ring stand.
• Never taste any chemical substances.

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 8 5

Name Date Class

LAB 2 CBL LABORATORY MANUAL

Pre-Lab 4. Turn on the CBL unit and the graphing calculator.

Choose ChemBio from the list of programs. Press
1. Read over the entire laboratory activity. Write ENTER on the calculator twice.
balanced chemical equations for the dissociation 5. Choose SET UP PROBES from the MAIN
of NaCl, MgCl2 and AlCl3 in water. Form a MENU. Enter 1 as the number of probes. On the
hypothesis as to which of these compounds SELECT PROBES menu, choose CONDUCTIV-
would conduct the most electricity and the least ITY. Enter 1 as the channel number. Then select
electricity. Record your hypothesis on the next USE STORED from the CALIBRATION menu
page. and select H 0-2000 MICS from the CONDUC-
2. Which of the following substances would be con- TIVITY menu. Make sure the switch on the box
sidered ionic? Which would be nonionic? Explain is set to the same value.
your reason for each answer. 6. From the MAIN MENU, select COLLECT
a. potassium chloride (KCl) DATA. On the DATA COLLECTION menu,
b. methanol (CH3OH) select TRIGGER PROMPT. Allow the unit to
c. glucose (C6H12O6) warm up and then press ENTER.
d. hydrochloric acid (HCl)
e. zinc oxide (ZnO)
Part B: Comparing Ionic Compounds
3. Sketch a diagram of NaCl dissolving in water.
1. Label three beral pipettes—NaCl, MgCl2, and
AlCl3. Fill one of the pipettes with the 1.0M solu-
Procedure
tion of NaCl. Fill the other two pipettes with
Part A: Preparing the CBL System 1.0M MgCl2 and AlCl3, respectively.
If your teacher has the CBL system set up, you may 2. Using the 100-mL graduated cylinder, measure
skip to Part B. 70 mL of distilled water into the 150-mL beaker.
1. Set up a ring stand, clamp, and CBL probe as Raise the beaker until the conductivity probe is in
illustrated in Figure A. the water. After the conductivity meter stabilizes,
press TRIGGER on the CBL unit.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

2. Plug the conductivity probe into the adapter cable
in channel 1 of the CBL unit. 3. Measure and record the conductivity of the dis-
tilled water in Data Table 1.
3. Connect the CBL unit to the graphing calculator
with a link cable. 4. Lower the beaker and place 1 drop of NaCl solu-
tion into the distilled water. Stir with the glass
stirring rod and then raise the beaker until the
Figure A conductivity probe is in the solution. After the
Ring stand
conductivity meter stabilizes, press TRIGGER on
Conductivity
Test-tube the CBL unit. Measure and record the conductiv-
probe
clamp ity of this solution in Data Table 1.
5. Adding 1 more drop of the NaCl solution, repeat
step 4. Continue adding 1 drop and recording its
Graphing conductivity until a total of 8 drops of NaCl solu-
calculator CBL unit Beaker tion has been added.
6. If a TI-83 graphing calculator is being used, or
another type of graphing calculator and a com-
puter is available, refer to Appendix A for
instructions on how to convert this data into
graphical analysis.
7. After transferring the data to the graphing pro-
Link gram, rinse out the beaker with distilled water
cable and repeat steps 4–6 two more times using MgCl2

6 Chemistry: Matter and Change • Chapter 8 CBL Laboratory Manual

 Name Date Class

LAB 2 CBL LABORATORY MANUAL

and AlCl3, respectively. Be sure to transfer the 4. Use the conductivity probe to monitor the con-
data to the graphing program and rinse out the ductivity of the sodium chloride solution. Record
beaker after each substance. Rinse the conductiv- the conductivity in Data Table 2.
ity probe with distilled water in between each 5. Rinse the probe with distilled water.
substance. (Do this by spraying the probe over
6. Use the conductivity probe to monitor the con-
the 400-mL beaker or sink.)
ductivity of the sucrose solution. Record the
conductivity in Data Table 2.
Part C: Comparing Ionic and Molecular
Substances
Cleanup and Disposal
1. In two separate weighing dishes, measure 10 g
of sodium chloride (NaCl) and 10 g of sucrose 1. Disconnect the conductivity probe from the CBL
(C12H22O11). unit.
2. Using the 100-mL graduated cylinder, place 2. Rinse the probes with distilled water.
50 mL of distilled water in each of two 150-mL 3. Rinse out the beakers with distilled water.
beakers. Label one of the beakers sodium chlo- 4. Clean up your lab area and wash your hands.
ride (NaCl) and the other beaker sucrose Replace the lab equipment to the appropriate area.
(C12H22O11).
3. Pour the solid sodium chloride and sucrose into Hypothesis
the appropriate beakers and stir with a glass
stirring rod.

Data and Observations

Data Table 1 (to be used if graphing program not available)
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

NaCl conductivity MgCl2 conductivity AlCl3 conductivity

Drops (microsiemens) (microsiemens) (microsiemens)

Data Table 2
Substance Conductivity

Sodium chloride (NaCl)

Sucrose (C12H22O11)

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 8 7

Name Date Class

LAB 2 CBL LABORATORY MANUAL

Analyze and Conclude

1. Observing and Inferring Which solution was the best conductor of electricity? Explain.

2. Making and Using Graphs Make a graph of conductivity versus concentration. Plot
conductivity on the y-axis and concentration (number of drops) on the x-axis. If you used a
graphing program, you may use those graphs. Draw a line of best fit for each of these sets
of data.

3. Observing and Inferring For each of the dissociation reactions of NaCl, MgCl2 and
AlCl3, what is the ratio of number of electrons transferred in each reaction? How does this

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

explain the graphs drawn in question 2?

4. Drawing a Conclusion How does the conductivity of sodium chloride compare with
sucrose? Why is this the case?

Real-World Chemistry
What types of substances make good conductors of electricity? What element is used to
bring electricity to the places where we live? Why is this an effective substance?

8 Chemistry: Matter and Change • Chapter 8 CBL Laboratory Manual

 Name Date Class

LAB 3 CBL LABORATORY MANUAL

Use with
Melting and Freezing Points Section 13.4

W hen you add heat to a substance, the average kinetic energy of

the particles in the substance increases. If enough energy is
added, the particles overcome the attractive forces holding the particles
together and the substance changes state—from a solid to a liquid, or
even to a gas. As this happens, the movement of the particles becomes
more random. By contrast, as substances lose heat, the interactions
between particles increases and the particles become more ordered.
The temperature of a substance stays the same during any change of
state, or phase change. The energy absorbed by the system is used to
overcome intermolecular attractions, not to increase the kinetic energy
(temperature) of the substance. In this lab, you will determine the
melting/freezing point for water and a food preservative, BHT
(butylated hydroxytoluene, C15H24O).

Problem Objectives Materials

What are the melting/ • Describe the process of CBL unit 400-mL beaker
freezing points of water melting and freezing. TI graphing 25-mL graduated
and BHT (C15H24O)? • Determine the melting calculator cylinder
and freezing points of link cable 20  150-mm test
two substances. temperature probe tube
• Predict which substance AC adapter hot plate
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

will have a higher or BHT ring stand

lower melting/freezing salt (NaCl) clamp
point. ice glass stirring rod
water

Safety Precautions
• Always wear safety goggles and a lab apron.
• Use caution when working with the hot plate.
• Never taste any of the chemicals used in the lab.
• Do not touch the salt–ice solution. It will be extremely cold.
• Dispose of materials as your teacher instructs.

Pre-Lab
1. Read the entire laboratory activity. Sketch a 3. Using your textbook, look up the heating curve
representation of the solid, liquid, and gaseous for water. Describe each portion of the curve and
states of matter. explain why it has that particular shape.
2. What terms are used to describe the following
phase changes: solid to liquid; liquid to gas; solid
to gas; gas to liquid; liquid to solid?

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 13 9

Name Date Class

LAB 3 CBL LABORATORY MANUAL

Procedure 6. Now lower the test tube of water into the beaker
of ice water and press ENTER on the calculator
Part A: Preparing the CBL System
to begin data collecting.
1. Connect the CBL unit to the temperature probe, 7. After lowering the test tube, add 5 spoonfuls of
as shown in Figure A. Make sure the tempera- salt to the beaker and stir with a stirring rod.
ture probe is in channel 1. Then, using a link Continue to stir the ice water.
cable, connect the CBL unit to the graphing cal-
8. During data collection, slowly stir the water in
culator.
the test tube containing the temperature probe.
2. Turn on the CBL unit and the graphing calcula- If all the ice in the beaker melts, add additional
tor. Press the PRGM button on the calculator pieces of ice to the beaker.
and choose ChemBio from the list of programs.
9. Once crystals begin to form in the water, stop
Press ENTER on the calculator twice.
stirring and let the probe freeze in the water.
3. Choose SET UP PROBES from the MAIN After 20 minutes, the CBL will stop collecting
MENU. Enter 1 as the number of probes. data. If you think the lab is complete before
On the SELECT PROBES menu, choose 20 minutes, you may stop the run by pressing
TEMPERATURE. Enter 1 as the channel the <ON> button of the calculator to stop the
number. Select USE STORED from the program.
CALIBRATION MENU.
10. See page v for sending data for graphical
analysis.
Part B: Collecting Freezing Point Data
11. On the displayed graph, analyze the flat part of
1. Fill a 400-mL beaker half full with ice, and then the curve to determine the freezing temperature
add 100 mL of water. of water. Save your data.
2. Put 5–7 mL of water into a test tube and set up
the apparatus as shown in Figure A. Do not
Ring stand
lower the test tube of water into the ice water with clamp
until you have set up the calculator for data

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

collection. (See step 3.)
Test tube
3. From the MAIN MENU, select COLLECT with water
DATA. On the DATA COLLECTION menu, Temperature
or BHT
select TIME GRAPH. Enter 15 as the time probe
(in s) between samples and then enter 80 as the
number of samples. The CBL unit will collect Graphing CBL unit
data for 20 min. calculator
Beaker with
4. Press ENTER; then select USE TIME SETUP ice water
to continue. Note: If you want to change the
sample time or sample number you entered,
select MODIFY SETUP.
5. Enter 15 as the minimum temperature (Ymin)
and 100 as the maximum temperature (Ymax).
Enter 1 as the temperature increment (Yscl). Link
cable
Figure A

10 Chemistry: Matter and Change • Chapter 13 CBL Laboratory Manual

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LAB 3 CBL LABORATORY MANUAL

Part C: Collecting Melting Point Data Cleanup and Disposal

1. Set up the CBL for taking data as in steps 3–5 1. Dispose of the salt–ice solution following your
of Part B. teacher’s directions.
2. Take the test tube of frozen water out of the ice 2. Place the BHT test tube in the hot-water bath
bath and place it in the hot-water bath. Heat the your teacher has prepared.
test tube slowly. Allow the CBL to take data
3. Clean up the lab area and wash your hands with
until the water has completely melted. Follow
directions on page X to save your data. soap or a detergent.

Part D: Collecting BHT Data Data and Observations

Obtain a BHT test tube that your teacher has pre- Data Table 1
pared for you. Repeat parts B and C using the BHT. Freezing Melting
Substance point (°C) point (°C)

Water

BHT

Analyze and Conclude

1. Observing and Inferring What is the freezing point of water? Of BHT? What evidence
do you have?
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

2. Collecting and Interpreting Data What is the relationship between melting point and
freezing point? Explain your answer.

3. Recognizing Cause and Effect Use the concept of molecular motion to describe why
the temperature does not change during a phase change.

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 13 11

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LAB 3 CBL LABORATORY MANUAL

4. Drawing a Conclusion Look at the structures of water and of BHT. Suggest an

explanation for the differences in their melting/freezing points.

5. Thinking Critically What role did the salt play in this investigation?

Real-World Chemistry
1. How could a scientist know if he or she had 2. Why does ice float in a glass of water?
pure water or pure BHT based on the tests you
just completed?

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

12 Chemistry: Matter and Change • Chapter 13 CBL Laboratory Manual

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LAB 4 CBL LABORATORY MANUAL

Use with
Boyle’s Law Section 14.1

S uppose you have a basketball containing a given volume of air. If

you were to sit on the ball, its volume would decrease. What
happens to the particles of air inside the ball? They would be forced
to occupy a smaller volume. Because the particles are more crowded,
collisions among particles and between the particles and the inside
surface of the ball increase. This increase in the number of collisions
causes an increase in pressure inside the ball. The relationship
between the volume of a gas and the pressure it exerts is known as
Boyle’s law, and it can be studied in a laboratory setting.

Problem Objectives Materials

What is the relationship • Collect data that relate CBL unit
between the volume and pressure to volume. TI graphing
pressure in a closed system? • Analyze laboratory data calculator
and develop a mathemat- link cable
ical expression to show AC adapter for CBL
the relationship between unit
pressure and volume. CBL-DIN adapter
• Calculate pressure of an gas pressure sensor
unknown gas. syringe
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

Safety Precautions
• Always wear safety goggles and a lab apron.
• Use caution when pushing on syringe.
• Use caution when making electrical connections.

Pre-Lab
1. Sketch three syringes at equal temperature and 2. What is the definition of pressure, volume, and
containing an equal number of gas particles. temperature?
Show the plungers at three different volumes— 3. Read over the entire laboratory activity. Form
5 mL, 15 mL, and 20 mL. Use dots to represent a hypothesis as to how volume and pressure
the gas particles. How do the contents of the three are related in a closed system. Record your
syringes appear to be different? How does the hypothesis on page 14.
pressure differ in the three syringes?
4. What variables are changed in this lab? What is
held constant?

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 14 13

Name Date Class

LAB 4 CBL LABORATORY MANUAL

Figure A
DIN adapter
CBL
TI calculator unit

Gas pressure
sensor

Syringe

AC adapter
for CBL unit
Link cable

Procedure 2. Press the plunger of the syringe down to the 5 mL

mark. When the pressure gauge stops changing,
Part A: Preparing the CBL System
press TRIGGER on the CBL unit. Enter 5 as the
1. Connect the syringe to the gas pressure sensor. mL on the graphic calculator.
Then connect the CBL unit to both the gas pres- 3. From the DATA COLLECTION menu, select
sure sensor and the graphing calculator as shown MORE DATA.
in Figure A. Make sure the gas pressure sensor
4. Repeat steps 1 through 3, pressing the plunger
probe is in channel 1.
of the syringe down to the 7.5 mL, 10.0, mL,
2. Turn on the CBL unit and the graphing calculator. 12.5 mL, 15.0 mL, 17.5 mL, and 20.0 mL marks.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

Press the PRGM button on the calculator and
5. After the last set of data, select STOP AND
choose ChemBio from the list of programs. Press
GRAPH.
ENTER on the calculator twice.
6. Select GRAPH on your calculator to see a line
3. Choose SET UP PROBES from the MAIN
graph. Press STAT and then choose EDIT. The
MENU. Enter 1 as the number of probes. On the
data are now displayed. Volume will be in
SELECT PROBES menu, choose PRESSURE.
Column 1 and pressure will be in Column 2.
Enter 1 as the channel number. Then select USE
Record these data in Data Table 1.
STORED from the CALIBRATION menu and
select ATM for your units. You will be returned to
the MAIN MENU. Cleanup and Disposal
4. From the MAIN MENU, select COLLECT Disconnect the sensor from the CBL unit. Following
DATA. On the DATA COLLECTION menu, your teacher’s directions, return all equipment to its
select TRIGGER PROMPT. Follow the directions proper place.
on the calculator to collect data.
Hypothesis
Part B: Collecting Data
1. Open the blue valve between the atmosphere and
the syringe. Set the inside ring of the syringe to
the 20 mL mark and close the blue valve to the
atmosphere.

14 Chemistry: Matter and Change • Chapter 14 CBL Laboratory Manual

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LAB 4 CBL LABORATORY MANUAL

Data and Observations

Data Table 1
Volume (mL) Pressure (ATM) Constant (pv or p/v)

5.0

7.5

10.0

Analyze and Conclude

1. Collecting and Interpreting Data As the volume changes from 10 to 20 mL, what
happens to the pressure?

2. Observing and Inferring Is the relationship between volume and pressure an inverse or
a direct relationship?
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

3. Thinking Critically Why is the graph you see a curved line, not a straight line? What
mathematical function would you have to graph to achieve a straight line?

4. Predicting Predict what the pressure of the gas in the syringe would be if the volume
was increased to 40 mL.

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 14 15

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LAB 4 CBL LABORATORY MANUAL

5. Recognizing Cause and Effect Why was it necessary to keep temperature and number
of gas particles constant during this activity?

6. Error Analysis What could be done to improve the accuracy of this investigation?

Real-World Chemistry
1. Why would it be important for a scuba diver to 2. What are some common household products
be familiar with Boyle’s law? that utilize Boyle’s law?

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

16 Chemistry: Matter and Change • Chapter 14 CBL Laboratory Manual

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LAB 5 CBL LABORATORY MANUAL

Use with
Gay-Lussac’s Law Section 14.1

H ave you ever tried to bounce a cold basketball or walked outside

in the cold with a helium balloon? Why is it never advisable to
heat a sealed container? As you might predict, these items act in an
odd manner under different temperature conditions. Why does this
happen? In this lab, you will investigate the relationship between
temperature and pressure, as proposed by Joseph Gay-Lussac.

Problem Objectives Materials

What is the relationship • Develop a mathematical CBL unit
between the temperature expression to show the TI graphing calculator
and pressure of a sealed relationship between Vernier CBL pressure sensor (attached to
container of gas at a temperature and volume. rubber stopper assembly)
constant volume? • Determine a temperature- Vernier temperature probe
volume constant. 1000-mL beakers (3)
• Make calculations on 150-mL Erlenmeyer flask
unknown gases based ice
on a determined thermal mitt
temperature-volume hot plate
constant.

Safety Precautions
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

• Always wear safety goggles and a lab apron.

• Use caution when working around a hot plate and hot glassware.
• Use caution when making electrical connections.

Pre-Lab Procedure
1. What are temperature and pressure? Part A: Preparing the CBL System
2. Describe these three containers in relationship to 1. Connect the CBL unit to the pressure sensor and
each other in terms of particle speed and colli- temperature probe, as shown in Figure A. Make
sions with the walls of the container. All have sure the pressure sensor is in channel 1 and the
same amounts of the same gas in them. temperature probe is in channel 2. Use the link
a. 1-L container at 25°C cable to connect the CBL to the graphing
b. 1-L container at 150°C calculator.
c. 1-L container at 300°C 2. Turn on the CBL unit and the graphing calculator.
3. Read over the entire lab activity. What variables Press the PRGM button on the calculator and
will be held constant in this lab? choose ChemBio from the list of programs. Press
ENTER on the calculator twice.

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 14 17

Name Date Class

LAB 5 CBL LABORATORY MANUAL

3. Choose SET UP PROBES from the

MAIN MENU. Enter 2 as the number
of probes. On the SELECT PROBE
menu, choose PRESSURE. Enter 1 as
the channel number. Then select USE Channel 2 Channel 1
Erlenmeyer
STORED from the CALIBRATION Graphing flask
MENU and select ATM for your calculator
units. Pressure
sensor
4. On the SELECT PROBE menu, next
choose TEMPERATURE. Enter 2 as
the channel number. Then select USE
STORED from the CALIBRATION
MENU and select COLLECT DATA 1000-mL
from the MAIN MENU. On the CBL unit beaker
DATA COLLECTION MENU, select Link
TRIGGER prompt. Follow the direc- cable
tions on the calculator to collect data. Figure A

Part B: Collecting Data 6. After the temperature and pressure of the hot
1. Prepare three water baths:
water are recorded, carefully remove the flask
a. To prepare a boiling-water bath, pour about
and place it in the room-temperature beaker with
800 mL of water into a 1000-mL beaker and the temperature probe beside the flask in the
place it on a hot plate on high. water. Continue to monitor the CBL until it stabi-
b. To prepare an ice-bath, pour about 700 mL of
lizes and then press the TRIGGER button on the
cold tap water into a second 1000-mL beaker CBL unit.
and add ice. 7. Repeat steps 3–6 for the beaker with the ice

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

c. Pour about 800 mL of room-temperature water water. Ask your teacher whether you should take
into a third 1000-mL beaker. more data points. After three data points, press
2. Insert the rubber stopper assembly, connected to END to stop collecting data.
the pressure sensor, into the 150-mL Erlenmeyer 8. Select GRAPH on your calculator. Press STAT
flask, with the valve open to the atmosphere. and then choose EDIT. The data are now dis-
Twist the stopper into the flask to insure a tight played. Record these data in Data Table 1.
fit. Close the valve to the atmosphere. If the stop-
per pops out at any time during the experiment, Cleanup and Disposal
you must start over. Begin with the hot water to
prevent this. 1. Turn off your hot plate and unplug it.

3. Carefully place the stoppered Erlenmeyer flask 2. Turn off the calculator and the CBL unit, and
into the hot-water bath with the temperature then unplug them.
probe in the beaker of water next to but not in the 3. Return the CBL unit and the probes to the
flask, as illustrated in Figure A. appropriate location.
4. Now press ENTER on the calculator to begin 4. Clean up and organize your lab area.
monitoring pressure and temperature.
5. After the temperature and a pressure have stabi-
lized, press the TRIGGER button on the CBL
unit. This will store the temperature and pressure
in the list on the calculator. Follow the calculator
directions to take more data.

18 Chemistry: Matter and Change • Chapter 14 CBL Laboratory Manual

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LAB 5 CBL LABORATORY MANUAL

Data and Observations

Data Table 1
Trial Pressure (atm) Temperature (°C) Temperature (K) Constant (P  T or P/T)

Analyze and Conclude

1. Measuring and Using Numbers Convert the Celsius temperatures to kelvin. Record
these temperatures in Data Table 1.
2. Observing and Inferring Is the relationship between temperature and pressure a direct
or an inverse relationship? Explain your answer.

3. Measuring and Using Numbers Determine a constant for this relationship. Is it P  T

or P/T?

4. Predicting What would the pressure of the gas in the container be if the temperature
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

was 33°C?

5. Observing and Inferring Why was it necessary to keep the volume constant during this
experiment?

Real-World Chemistry
1. Why is it necessary for a hot-air balloonist, 2. During which season should motorists keep
who is traveling around the world, to be famil- more air in their tires—winter or summer?
iar with Gay-Lussac’s law?

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 14 19

 Name Date Class

LAB 6 CBL LABORATORY MANUAL

Use with
Determining Molar Mass Section 15.3

Using Freezing Point Depression

T he freezing point depression of a solution is a colligative

property of the solution. A temperature versus time graph can
be used to determine the freezing point of a particular substance. A
plateau occurs on the graph at the freezing point because no change
in average kinetic energy of the system takes place as the phase
change occurs. This allows the freezing point of a pure substance to
be compared with that of a solution. From this comparison, it is
possible to determine the molecular mass of an unknown substance.
In this lab, an organic solute will be used to determine a freezing
point depression constant for the food additive BHT (butylated
hydroxytolune). Using this information, you will determine the
molecular mass of an unknown substance.

Problem Objectives Materials

What is the molecular mass • Describe the process of CBL unit unknown substance
of an unknown substance? melting and freezing. TI graphing 400-mL beaker
• Collect data to determine calculator 1-mL graduated
the Kf for BHT. link cable cylinder
• Compare melting point temperature probe test tubes (2–3)
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

graphs to determine the adapter cable hot plate

molecular mass of the BHT (butylated ring stand
unknown substance. hydroxytoluene universal clamp
• Analyze the results and C15H24O) laboratory balance
complete an error PDB (para- copper wire stirrer
analysis. dichlorobenzene) scoop

Safety Precautions
• Always wear safety goggles and a lab apron.
• Use caution when working with the hot plate.
• Some of these chemicals are flammable and may have toxic vapors;
you may want to work in a fume hood.
• Dispose of materials as your teacher instructs.

Pre-Lab
1. Sketch the cooling curve for water and identify its 3. If 2.8 grams of NaCl is added to 50.0 grams of
key features. water, at what temperature would you expect the
2. What is molality? solution to freeze? (Density of water  1.0 g/cm3)

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 15 21

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LAB 6 CBL LABORATORY MANUAL

4. What is the molar mass of BHT? What is the 6. Press ENTER and then select USE TIME SETUP
molar mass of PDB? to continue. Note: If you wish to change the sam-
5. Read over the entire laboratory activity. Describe pling time or number of samples, select MODIFY
the process you will use to melt the pure solids. SETUP.
7. Enter 15 as the minimum temperature (Ymin),
Procedure 100 as the maximum temperature (Ymax), and 1 as
the temperature increment (Yscl).
Part A: Preparing the CBL System
1. Using the adapter cable, connect the CBL unit to Part B: Collecting Data
the temperature probe, as shown in Figure A.
1. Add approximately 300 mL of water to the
Make sure the temperature probe is in channel 1.
400-mL beaker and place the beaker on the hot
Then, using a link cable, connect the CBL unit to
plate. Turn on the hot plate and heat the water to
the graphing calculator
approximately 90°C.
2. Using a laboratory balance, measure the mass of
Adapter cable an empty test tube and record the value in Data
CBL
Table 1. Add about 8.0 g of BHT to the test tube.
unit TI graphing Measure the total mass of the test tube and BHT
calculator and record the measurement.
Temperature
probe
3. Use the clamp to suspend the test tube in the hot
water bath. After the BHT has melted completely,
reposition the clamp so the test tube is not over
the hot water bath or the hot plate. Place the tem-
perature probe into the BHT mixture and press
Test tube ENTER on the calculator to begin collecting data.
4. To maintain even cooling, stir the BHT continu-
ously using the copper wire stirrer.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

5. After the data collection is complete, make a
graph by transferring the data to a computer using
Link cable
Figure A the directions from page v.
6. Using the same BHT sample, add about 1.0 g of
para-dichlorobenzene (PDB) to the test tube.
2. Turn on the CBL unit and the graphing calculator.
Record the mass in Data Table 1. Repeat steps
Press the PRGM button on the calculator and
3–5 above. Be sure to stir the solution once it has
choose ChemBio from the list of programs. Press
all melted.
ENTER on the calculator twice.
7. Repeat steps 1–6 using a clean test tube, about
3. Choose SET UP PROBES from the MAIN
8.0 g of BHT, and about 1.0 g of the unknown.
MENU. Enter 1 as the number of probes. On the
Be sure the two substances are well mixed during
SELECT PROBES menu, choose TEMPERA-
the melting phase.
TURE. Enter 1 as the channel number.
4. Select USE STORED from the CALIBRATION Cleanup and Disposal
MENU.
5. From the MAIN MENU, select COLLECT 1. Dispose of or store the chemical as directed by
DATA. Select TIME GRAPH from the DATA your teacher.
COLLECTION MENU. Enter 15 as the time 2. Rinse the probes with distilled water. Dispose of
(in s) between samples and enter 60 as the the rinse water in an appropriate container.
number of samples. The CBL unit will collect 3. Clean up lab tables and wash your hands with
data for 15 minutes. soap or detergent before leaving the lab.

22 Chemistry: Matter and Change • Chapter 15 CBL Laboratory Manual

 Name Date Class

LAB 6 CBL LABORATORY MANUAL

Data and Observations

Data Table 1
Substance Mass (g)

Empty test tube 1

Test tube 1  BHT

Test tube 1  BHT  PDB

BHT

PDB

Empty test tube 2

Test tube 2  BHT

Test tube 2  BHT  unknown

BHT

Unknown

Calculate the masses of the BHT, PDB, and unknown substance.

Analyze and Conclude

1. Observing and Inferring Using the graphs, determine the melting point for each of the
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

following: pure BHT; BHT  PDB; BHT  unknown.

2. Collecting and Interpreting Data

a. What is the difference in freezing point between pure BHT and the solution of BHT
and PDB?

b. What is the difference in freezing point between pure BHT and the solution of BHT
and the unknown?

3. Measuring and Using Numbers Calculate the molality of the solution of BHT and
PDB (in mol solute/kg solvent).

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 15 23

Name Date Class

LAB 6 CBL LABORATORY MANUAL

4. Measuring and Using Numbers Calculate the freezing point depression constant Kf for
BHT. (Tf  Kf m)

5. Thinking Critically Why was a solvent with a large Kf value used in this activity?

6. Error Analysis Calculate the molecular mass of the unknown and compare it to the
actual molecular mass provided by your teacher. Calculate the percent error of the
experimentally determined molecular mass.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

Real-World Chemistry
1. How does antifreeze help cars in both the 2. Why do road crews in snowy climates keep a
winter and the summer? supply of CaCl2 on hand? Explain why CaCl2
works better than NaCl.

24 Chemistry: Matter and Change • Chapter 15 CBL Laboratory Manual

 Name Date Class

LAB 7 CBL LABORATORY MANUAL

Use with
Calorimetry Section 16.2

H eat is energy that is being transferred from a hot object to a

colder object. If you know how much heat a substance can
absorb and hold, the amount of energy transferred between two
substances can be determined. On a hot, sunny day, heat from the
Sun might go into a cool glass of lemonade and melt the ice. On a
cold winter day, heat may leave a hot cup of coffee and warm up the
air around it. In this lab, specific heat is used to follow the flow of
energy and to determine the temperature of a Bunsen burner flame.

Problem Objectives Materials

What is the temperature of • Diagram a flowchart CBL unit 100-mL graduated
a Bunsen burner flame? that depicts the flow TI graphing cylinder
of energy in this calculator Bunsen burner
experiment. link cable large plastic-foam
• Calculate the amount of AC adapter cup
energy transferred temperature probe tongs
between two systems. nickel coin matches

Safety Precautions
• Always wear safety goggles and a lab apron.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

• Be careful when working with an open flame, and tie back long hair.
• Once the nickel is heated, the tongs will be hot. Do not touch them.

Pre-Lab Procedure
1. What is the difference between heat and Part A: Preparing the CBL System
temperature? 1. Connect the CBL unit to the temperature probe,
2. What is meant by specific heat? What is the as shown in Figure A. Make sure the temperature
specific heat of water? Of nickel? probe is in channel 1. Then, using a link cable,
3. What equation can be used to calculate the connect the CBL unit to the graphing calculator.
amount of heat transferred between two 2. Turn on the CBL unit and the graphing calculator.
substances? Press the PRGM button on the calculator and
4. How much energy (in cal) would it take to raise choose ChemBio from the list of programs. Press
the temperature of 5.00 g of water from 20°C to ENTER on the calculator twice.
30°C? 3. Choose SET UP PROBES from the MAIN
5. Read the entire laboratory activity. Sketch a MENU. Enter 1 as the number of probes. On the
diagram to show the flow of heat. SELECT PROBES menu, choose TEMPERA-
TURE. Enter 1 as the channel number.

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 16 25

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LAB 7 CBL LABORATORY MANUAL

Figure A 4. Using tongs, hold the nickel in the Bunsen

CBL burner flame until it glows red. This should take
TI graphing
unit 3–5 min. If the nickel has been used previously,
calculator Temperature
it may not glow red.
probe
5. Now press ENTER on the graphing calculator to
begin monitoring temperature.
6. Place the temperature probe in the water in the
cup. Read the temperature and record the initial
temperature of the water in Data Table 1.
7. Leave the temperature probe in the water.
AC adapter Quickly, but carefully, take the nickel out of the
flame and drop it in the water. CAUTION: Do
Link cable not allow the hot nickel to touch the sides of
the cup. Carefully stir the water with the temper-
ature probe and monitor the temperature. Record
4. From the MAIN MENU, select COLLECT in Data Table 1 the highest temperature that the
DATA. On the DATA COLLECTION menu, water reaches.
select MONITOR. Do NOT press ENTER until 8. Pour out the water and the nickel into the sink.
you are ready to monitor the temperature. Repeat steps 1–7 using 60 mL of water and again
using 80 mL of water.
Part B: Collecting Data
1. Using a graduated cylinder, measure 40 mL of tap
Cleanup and Disposal
water and pour it into the cup. 1. Make sure the gas to the Bunsen burner is shut
2. Determine the mass of your nickel and record it off completely.
in Data Table 1. 2. Turn off and unplug the CBL unit.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

3. Turn on the gas and light the Bunsen burner. 3. Return all equipment to its proper place. Clean up
Create as hot a flame as possible. CAUTION: Be the lab area.
careful when working with an open flame, and
tie back long hair.

Data and Observations

Data Table 1
Initial Final Change in
Mass of Volume of temperature temperature temperature
Trial nickel (g) water (mL) of water (°C) of water (°C) of water, or T (°C)

26 Chemistry: Matter and Change • Chapter 16 CBL Laboratory Manual

 Name Date Class

LAB 7 CBL LABORATORY MANUAL

Analyze and Conclude

1. Using Numbers For each trial, determine the change in the water temperature, T, and
record it in Data Table 1. (T  Tfinal  Tinitial)
2. Observing and Inferring How much energy (in cal) was absorbed by the water in each
trial? How do your three results compare? (Specific heat of water is 1.00 cal/g°C.)
Assume the density of water is 1.00 g/mL.

3. Thinking Critically How much heat did the nickel lose in each trial?

4. Drawing a Conclusion Using the information from questions 2 and 3, what is the
temperature of the Bunsen burner flame?

5. Communicating Post your data on the board and compare it with the class data. What is
the average temperature calculated by your class for the Bunsen burner flame?
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

6. Error Analysis Compare your Bunsen burner flame temperature with the actual
temperature that your teacher gives you. How close were you? What might have been
some sources of error in this lab? What assumptions were made that may have caused
errors in your numbers?

Real-World Chemistry
1. Why might it be effective for homeowners to 2. How is a thermos bottle able to keep hot
use a water-heater blanket around the water liquids hot and cold liquids cold?
heaters in their homes?

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 16 27

 Name Date Class

LAB 8 CBL LABORATORY MANUAL

Use with
Hess’s Law Section 16.3

H ess’s law states that the heat gained or released in a chemical

reaction is the sum of the heat gained or released during the
individual steps of that reaction. In this lab, you will determine the
molar enthalpy of reaction (Hrxn) for three chemical reactions. Then,
you will use Hess’s law to verify the experimental value obtained for
one of these reactions.

Problem Objectives Materials

How can the enthalpy • Measure the heat CBL unit 2.0M NaOH
changes for two chemical absorbed or released in TI graphing 2.0M NH3(NH4OH)
reactions be used to obtain three chemical reactions. calculator 100-mL graduated
the enthalpy change for • Determine the molar link cable cylinders (2)
the reaction of ammonia enthalpy of each AC adapter thermometers (2)
with hydrochloric acid? reaction. temperature probe large plastic-foam
NH3(aq)  HCl(aq) 0 • Apply Hess’s law to verify 2.0M HCl cup
one of the experimental 2.0M NH4Cl glass stirring rod
NH4Cl(aq)
results.
Is this an exothermic or
endothermic reaction?

Safety Precautions
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

• Always wear safety goggles and a lab apron.

• Use caution when working with acids and bases.
• The reaction of ammonium chloride and sodium hydroxide releases
ammonia; the reaction should be performed in an operating fume
hood.

Pre-Lab
Then, using a link cable, connect the CBL unit to
1. Read the entire laboratory activity. Describe
the graphing calculator.
Hess’s law in your own words.
2. Turn on the CBL unit and the graphing calculator.
2. Describe how specific heat is used in calorimetry.
Press the PRGM button on the calculator and
3. Describe in your own words what is meant by H. choose ChemBio from the list of programs. Press
ENTER on the calculator twice.
Procedure 3. Choose SET UP PROBES from the MAIN
Part A: Preparing the CBL System MENU. Enter 1 as the number of probes. On the
SELECT PROBES menu, choose TEMPERA-
1. Connect the CBL unit to the temperature probe,
TURE. Enter 1 as the channel number. Select
as shown in Figure A. Plug the adapter cable
USE STORED from the CALIBRATION MENU.
into channel 1 of the CBL unit and then plug
a temperature probe into the adapter cable. Make
sure the temperature probe is in channel 1.

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 16 29

Name Date Class

LAB 8 CBL LABORATORY MANUAL

Figure A 6. Pour the HCl solution into the cup and insert
Adapter cable the temperature probe from the CBL unit. Press
ENTER to begin taking data. Then, cautiously
CBL
unit pour the NaOH solution into the cup while
TI graphing
calculator stirring with a glass stirring rod.
7. Have the CBL unit take data every 30 s for
Temperature
probe 4 min as the reaction continues. Continue to stir
the solution slowly and monitor the CBL unit
and calculator. If your calculator has a sleep
function, be sure to press a number button
occasionally to keep it from shutting off.
8. When the CBL unit has stopped taking data,
turn the CBL unit off and download the data
from the graphing calculator to the computer,
Plastic-foam cup following the instructions in Appendix A. Save
Link cable your data.
9. Using distilled water, thoroughly rinse the ther-
mometers and wash out the graduated cylinders.
Part B: Collecting Data Repeat steps 1–8 for reaction 2 using 50 mL of
2.0M NH4Cl with 50 mL of 2.0M NaOH.
1. For reaction 1, measure 50 mL of 2.0M HCl in
10. Thoroughly rinse the thermometers and gradu-
a 100-mL graduated cylinder. Measure 50 mL
ated cylinders again with distilled water and
of 2.0M NaOH in a second 100-mL graduated
repeat steps 1–8 for reaction 3 using 50 mL of
cylinder.
2.0M NH3 with 50 mL of 2.0M HCl.
2. From the MAIN MENU, select COLLECT
11. Download the data from the calculator to a
DATA. On the DATA COLLECTION MENU,
computer after each trial and save the data.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

select TIME GRAPH. Enter 30 as the time
(in s) between samples and then enter 3 as the
number of samples. The CBL unit will collect Cleanup and Disposal
data for 4 min. 1. Wash all solutions down the drain with plenty
3. Press ENTER, then select USE TIME SETUP of water.
to continue. Note: If you want to change the 2. Rinse the graduated cylinders.
sample time or sample number you entered,
select MODIFY SETUP. 3. Rinse the probes with distilled water.
4. Enter 0 as the minimum temperature (Ymin) and 4. Turn off the CBL unit and unplug it.
enter 50 as the maximum temperature (Ymax). 5. Return all equipment to its proper place, clean
Enter 1 as the temperature increment (Yscl). Do up the lab area, and wash your hands with soap
not hit ENTER to begin collecting data yet. or detergent.
5. Using two thermometers, measure the initial
temperatures of the two solutions and record
them in Data Table 1. If the two initial temper-
atures are less than 0.2°C apart, average the two
temperatures and use the average as the initial
temperature.

30 Chemistry: Matter and Change • Chapter 16 CBL Laboratory Manual

 Name Date Class

LAB 8 CBL LABORATORY MANUAL

Data and Observations

Data Table 1
Initial temperature Temperature directly after mixing
Reaction before mixing (Tinitial) (Tmix), derived from graph

Analyze and Conclude

1. Making and Using Graphs Make a graph of the data from each of the three trials. Plot
time (s) on the x-axis and temperature (°C) on the y-axis.
2. Acquiring and Analyzing Information Draw a best fit line through your data. The line
should intercept the y-axis. The point at which the line intercepts the y-axis is the
temperature directly after mixing (Tmix). Record Tmix in Data Table 1.
3. Measuring and Using Numbers Assume the density of the mixed solutions is
1.03 g/mL. Assume that the specific heat of the solutions is the same as the specific heat
of water, 4.18 J/g°C. Using the following equations, determine the enthalpy change for
each reaction.
a. Tsolution  Tmix  Tinitial
b. qreaction  (grams of solution  specific heat of solution  Tsolution)
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

4. Measuring and Using Numbers What is the molar enthalpy for each of the three
reactions in kJ/mol?

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 16 31

Name Date Class

LAB 8 CBL LABORATORY MANUAL

5. Observing and Inferring Rearrange the equations for reactions 1 and 2 to obtain the
equation for reaction 3. Determine the change in enthalpy for reaction 3. Compare this
result with the enthalpy change you obtained by direct measurement.

6. Classifying Classify reactions 1, 2, and 3 as exothermic or endothermic.

7. Error Analysis Every measurement involves a certain amount of error. Which of the
two values for H for reaction 3 is likely to have the greater error? What is the largest
source of error in this lab?

Real-World Chemistry
Explain how cold packs and hot packs work.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

32 Chemistry: Matter and Change • Chapter 16 CBL Laboratory Manual

 Name Date Class

LAB 9 CBL LABORATORY MANUAL

Use with
Determine the Molar Mass Section 19.4

of an Unknown Acid

A ccording to the Arrhenius definition of acids and bases, acids are

substances that produce hydrogen ions (H) in solution, and
bases are substances that produce hydroxide ions (OH) in solution.
When an acid and a base combine, the hydrogen ions from the acid
react with the hydroxide ions from the base to form water—a
neutralization reaction.
In a neutralization reaction, moles of H ions equal moles of OH
ions. This relationship is the basis for the procedure called titration,
which you will use to standardize a base solution. Standardizing a
base means determining its molar concentration. You will then use
your standardized base to determine the molar mass of an acid. To
determine when the moles of H equal the moles of OH, you will
monitor the pH of an acid solution as a solution of base is added
slowly. The pH will rise suddenly when the concentrations of the two
ions are equal (the equivalence point).

Problem Objectives Materials

What is the molar mass of • Standardize a sodium CBL unit 250-mL Erlenmeyer
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

an unknown acid? hydroxide solution. pH probe flask

• Determine the molar TI graphing 50-mL burette
mass of an unknown acid calculator wash bottle with
using titration data. link cable distilled water
potassium hydrogen funnel
phthalate (KHP) ring stand
NaOH solution weighing paper or
unknown acid dish
phenolphthalein microspatula or
solution scoop
250-mL beakers (2) balance, sensitive
burette clamp
utility clamp

Safety Precautions
• Always wear safety goggles and a lab apron.
• Use caution when working with acids and bases.
• Wipe up any water spills to avoid slipping.

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 19 33

Name Date Class

LAB 9 CBL LABORATORY MANUAL

Pre-Lab Figure A
Burette
1. Define the following terms: (a) acid, (b) base, pH probe
(c) neutralize, (d) titration, and (e) pH.
Graphing
2. Write a balanced equation for the dissociation of Burette
calculator
clamp
(a) HCl, (b) H2SO4, (c) NaOH, (d) Mg(OH)2
3. Read the entire laboratory activity. Write
the balanced chemical equation for each of the Ring
CBL stand
following: unit
a. hydrochloric acid (HCl) reacts with sodium
hydroxide (NaOH)
b. sulfuric acid (H2SO4) reacts with sodium Erlenmeyer
hydroxide (NaOH) flask

Procedure
Part A: Preparing the CBL System 5. Using a weighing dish, measure 0.4–0.6 g of
potassium hydrogen phthalate (KHP). Record
1. Connect the CBL unit to the pH probe. Make sure the mass of KHP in Data Table 1. Transfer the
the pH probe is in channel 1. Then, using a link KHP to a 250-mL Erlenmeyer flask. With a
cable, connect the CBL to the graphing calcula- wash bottle filled with distilled water, rinse any
tor. residue from the weighing dish into the flask.
2. Turn on the CBL unit and the graphing calculator. 6. Add about 40 mL of distilled water to the
Press the PRGM button on the calculator and Erlenmeyer flask and swirl until the solid KHP
choose ChemBio from the list of programs. Press is completely dissolved. Then add 3 drops of
ENTER on the calculator twice. phenolphthalein to the acid in the flask.
3. Choose SET UP PROBES from the MAIN 7. From the MAIN MENU, select COLLECT

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

MENU. Enter 1 as the number of probes. On the DATA. On the DATA COLLECTION MENU,
SELECT PROBES menu, choose pH. Enter 1 as select TRIGGER PROMPT. Follow the direc-
the channel number. Select USE STORED from tions on the calculator to collect data.
the CALIBRATION MENU.
8. Insert the pH probe into the KHP solution.
When the pH meter is stable, press TRIGGER
Part B: Standardizing NaOH
on the CBL unit.
1. Set up the burette, burette clamp, 250-mL 9. The calculator will read VALUE? Enter 0 for
Erlenmeyer flask, the CBL, and pH probe for the volume of NaOH that has been added. This
titration as shown in Figure A. will give you the initial pH value.
2. Pour about 70 mL of NaOH solution into a 10. From the DATA COLLECTION MENU, select
250-mL beaker. MORE DATA. Add 1 mL of NaOH from the
3. Using a funnel, carefully fill the burette to the burette to the Erlenmeyer flask while swirling.
zero line with the NaOH solution. After the pH has stabilized once more, press
4. To eliminate any air in the burette tip, allow a TRIGGER on the CBL unit and enter 1 for the
little of the NaOH solution to run through the tip number of mL of NaOH added. Always enter
into a 250-mL waste beaker. Then refill the the total volume of NaOH that has been added
burette to the zero line. to the Erlenmeyer flask.

34 Chemistry: Matter and Change • Chapter 19 CBL Laboratory Manual

 Name Date Class

LAB 9 CBL LABORATORY MANUAL

11. Continue to add the NaOH solution 1 mL at a Part C: Titrating an Unknown Acid
time and take pH readings after each addition,
1. Fill the burette to the zero line with your stan-
until the pH begins to change. Then, add the
dardized NaOH solution.
NaOH solution by 0.5 mL and finally, by
1-drop increments until the pH rises quickly. 2. Using a clean weighing dish, measure 0.3–0.4 g
This is the equivalence point. Record in Data of the unknown acid into a 250-mL Erlenmeyer
Table 1 the total volume of NaOH used at this flask. Rinse any residue into the flask. Record the
point. mass in Data Table 2.
12. After you have reached the equivalence point, 3. Dissolve the unknown acid in about 40 mL of
add a few more mL of NaOH, making pH distilled water. Swirl to completely dissolve the
measurements after every 1 mL addition. If no acid.
more change occurs, the titration is complete. 4. Titrate the unknown acid following the procedure
Note the color of the solution in the beaker. described in steps 2–13 of Part B. Record the vol-
13. Download your data to the computer following ume of NaOH solution in Data Table 2.
the procedure in Appendix A.
14. Rinse the 250-mL Erlenmeyer flask. Repeat Cleanup and Disposal
steps 2–13 as many times as your teacher 1. Rinse the beakers and Erlenmeyer flask with
directs. plenty of water.
15. Use your data to calculate the concentration of 2. If not being used again, empty the burettes and
the NaOH. Use the class average of this con- clean them according to your teacher’s directions.
centration for Part C of this activity.
3. Disconnect the pH sensor and TI graphing calcu-
lator from the CBL unit. Following your teacher’s
directions, return all equipment to its proper
place.
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

Data and Observations

Data Table 1: Standardization of Base (Molar Mass of KHP  204.2 g/mol)
Concentration
Mass of KHP Mol KHP Volume of NaOH (L) Mol NaOH of NaOH (mol/L)

Data Table 2: Molar Mass of Unknown Acid

Molar mass
Volume of Concentration Mol of Mass of of unknown
NaOH (L) of NaOH (mol/L) Mol NaOH unknown acid unknown acid (g) acid (g/mol)

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 19 35

Name Date Class

LAB 9 CBL LABORATORY MANUAL

Analyze and Conclude

1. Measuring and Using Numbers KHP has one ionizable H ion per mole of KHP.
What is the ratio of moles of NaOH to moles of KHP in this reaction?

2. Measuring and Using Numbers Determine the concentration of the NaOH solution and
record it in the appropriate space in Data Table 1.

3. Acquiring and Analyzing Information In Part C, how many moles of NaOH did it
take to neutralize the unknown acid? Your teacher will tell you how many ionizable hydro-
gen atoms are in your unknown acid. What is the molar ratio of acid to base for this
reaction? What is the molar mass of the unknown acid?

4. Error Analysis Your teacher will give you the molar mass of the unknown acid.
Determine your percent error for this experiment.

5. Error Analysis If the following errors occurred, how would your calculated
concentration of the NaOH solution compare to the actual concentration?

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

a. The mass of the acid was measured correctly, but some of it was spilled on the counter
when transferring it to the Erlenmeyer flask.

b. Although not noticed, some of the NaOH was spilled on the counter, instead of going
into the flask with the acid.

Real-World Chemistry
1. Why is it important to monitor the pH levels of 2. Name some common antacids and describe
lakes, ponds, rivers, and streams? what ingredients make them work. How do
they help upset stomachs?

36 Chemistry: Matter and Change • Chapter 19 CBL Laboratory Manual

 Name Date Class

LAB 10 CBL LABORATORY MANUAL

Use after
Reaction Potentials of Metals Section 21.1

A voltaic cell is a device that converts chemical energy to electrical

energy. This is done by harnessing the electron flow generated by
a spontaneous redox reaction. A voltaic cell consists of two half-cells
connected by a conducting wire and a salt bridge. One half-cell, called
the anode, contains a metal in a solution of its ions and is the site of
oxidation. The other half-cell, called the cathode, contains a different
metal in a solution of its ions and is the site of reduction. The
conducting wire carries the flow of electrons. The salt bridge allows ions
to flow from one side to the other so the redox reaction can continue.
In this lab, a voltage probe is used to measure the flow of electrons
through voltaic cells made of different metals. The metal attached to
the positive lead of the voltage probe is the cathode and has a higher
reduction potential. The metal attached to the negative lead is the
anode and has a lower reduction potential. The reduction potentials of
five metals will be compared, resulting in a chart for understanding the
potentials of metals.

Problem Objectives Materials

Rank a series of different • Measure the amount CBL unit iron sulfate
metals from lowest reduc- of current flowing TI graphing (FeSO4)
tion potential to highest between two half-cells calculator 1  1-cm pieces of
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

reduction potential. How of a reaction. voltage probe the following

can the cell potential for • Predict the cell potentials link cable metals:
two half-reactions be of a two-metal system. adapter cable copper
calculated? • Analyze the data in 1M solution of each zinc
order to rank the metals of the following: lead
from a high reduction sodium nitrate silver
potential to low (NaNO3) iron
reduction potential. copper sulfate large watch glass
(CuSO4) forceps
zinc sulfate scissors
(ZnSO4) sandpaper
lead nitrate filter paper
(Pb(NO3)2)
silver nitrate
(AgNO3)

Safety Precautions
• Always wear safety goggles and a lab apron.
• Use caution with sharp edges of metals.
• AgNO3, CuSO4, Pb(NO3)2, and FeSO4 are toxic by ingestion; ZnSO4 and
Pb(NO3)2 may cause skin and eye irritation; AgNO3 will stain skin and
clothes.
• Use forceps to handle the metals.

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 21 37

Name Date Class

LAB 10 CBL LABORATORY MANUAL

Pre-Lab Figure A Cut along

dotted lines
1. Read over the entire laboratory activity. Define
reduction and oxidation.
Pb
2. Write the half-reaction for (a) the oxidation of
zinc; (b) the reduction of copper.
3. What happens at the anode? What happens at the
cathode?
Zn Ag
4. In which direction do electrons flow in a voltaic
cell? NaNO3
solution
5. Review the equation to calculate the potential of a
voltaic cell.

Procedure
Cu Fe
Part A: Preparing the CBL System
1. Connect the CBL unit to the voltage probe. Plug
the adapter cable in channel 1 and then plug the Filter paper
voltage probe into the adapter cable. Using a link
cable, connect the CBL unit to the graphing cal-
culator. 3. Label the ends of the filter paper with the metal
2. Turn on the CBL unit and the graphing calculator. strips to be tested (See Figure A).
Press the PRGM button on the calculator and 4. Place several drops of NaNO3 solution in the
choose ChemBio from the list of programs. Press middle of the paper with trails of this NaNO3
ENTER on the calculator twice. solution leading out to each end of the paper. If
3. Choose SET UP PROBES from the MAIN the NaNO3 center and trails begin to dry out,

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

MENU. Enter 1 as the number of probes. On the reapply the NaNO3 solution throughout the
SELECT PROBE MENU, choose VOLTAGE. activity.
Enter 1 as the channel number. Select COLLECT 5. Next, place 3 drops of the metal ion solutions on
DATA from the MAIN MENU. the corresponding areas of the filter paper (indi-
4. From the DATA COLLECTION menu, select cated by the name of the metal).
MONITOR INPUT. The voltage reading is now 6. Using tongs, place the corresponding metal piece
displayed on the screen. No readings will be on top of the solution. Always keep the top of the
stored in the MONITOR INPUT mode. metal dry. Note: If the metal has oxidized, shine
it with sandpaper first.
Part B: Data Collecting
7. Using copper as a reference metal, compare the
1. Obtain a 1  1-cm piece of each of the following potential of the other four metals with that of
metals: copper, zinc, lead, silver, and iron. Also copper. To do this, place the positive lead of the
obtain dropper bottles with 1M solutions of cop- voltage probe on copper and the negative lead on
per sulfate (CuSO4), zinc sulfate (ZnSO4), lead the metal being tested. If the voltage reads nega-
nitrate (Pb(NO3)2), silver nitrate (AgNO3), and tively, reverse the leads. Wait about 5 s and record
iron sulfate (FeSO4) the voltage of each of the metals compared with
2. Set up the equipment for the investigation. Draw copper in Data Table 1. Test the following com-
dashed lines on the filter paper, as indicated in binations: Cu and Zn, Cu and Pb, Cu and Ag, and
Figure A. Cut out the triangular areas between Cu and Fe.
the dashed lines and place the filter paper on top
of the watch glass.

38 Chemistry: Matter and Change • Chapter 21 CBL Laboratory Manual

 Name Date Class

LAB 10 CBL LABORATORY MANUAL

8. Because copper was the reference metal, assign 10. Test the following combinations: Zn and Pb, Zn
it an arbitrary reduction potential of zero. Rank and Ag, Zn and Fe, Pb and Ag, Pb and Fe, and
the metals in order of lowest reduction potential Ag and Fe.
(most negative) to highest reduction potential
(most positive) in Data Table 2. If the test Cleanup and Disposal
metal was connected to the negative lead, then
the voltage should be listed above copper and 1. Dispose of silver and lead products in waste
given a negative value. If the test metal was containers designated by your teacher.
connected to the positive lead, then the voltage 2. Place all metal pieces in a solid-waste container.
should be listed below copper and assigned a 3. Throw away filter paper and clean up the lab
positive value. area. Wash your hands before leaving the lab.
9. Before experimenting further, predict the poten- 4. Disconnect the sensor from the CBL unit. Turn
tial for the combinations given in Data Table 3. off the CBL unit and graphing calculator,
Use the information from Data Table 2 to make unplug them, and return all equipment to its
your predictions. Determine the actual poten- proper place.
tials of these combinations of metals.
Remember to keep the voltage positive and
keep the NaNO3 moist.

Data and Observations

Data Table 1 Data Table 2
Metals used Voltage Reduction potential
Metal (lowest to highest)
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

Cu/Zn

Cu/Pb

Cu/Ag

Cu/Fe

Data Table 3
Metal Predicted potential Measured potential Percent error

Zn/Pb

Zn/Ag

Zn/Fe

Pb/Ag

Pb/Fe

Ag/Fe

CBL Laboratory Manual Chemistry: Matter and Change • Chapter 21 39

Name Date Class

LAB 10 CBL LABORATORY MANUAL

Analyze and Conclude

1. Collecting and Interpreting Data Which metal in this experiment loses electrons most
readily? Which element gains electrons most readily?

2. Observing and Inferring How do your answers in question 1 help explain the data that
were recorded during this lab?

3. Formulating Models Sketch a diagram of the flow of electrons for one of the voltaic cells
made in the lab. Be sure to label the electrons, reduction, oxidation, cathode, and anode.

Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

4. Thinking Critically What is the function of the NaNO3-soaked filter paper?

5. Error Analysis What may have caused any errors found in this lab?

Real-World Chemistry
1. How do lead storage batteries produce an 2. Look up a reference table of reduction poten-
electric current? tials. Why might they differ from your values?

40 Chemistry: Matter and Change • Chapter 21 CBL Laboratory Manual

 CREDITS
Art Credits
Navta Associates: 2, 14, 18, 22, 26, 30; MacArt Design: 6, 10, 18, 34, 38
Copyright © Glencoe/McGraw-Hill, a division of the McGraw-Hill Companies, Inc.

CBL Laboratory Manual Chemistry: Matter and Change 41