7th Grade Science Unit:
ABC: Acid Base Chemistry
Unit Snapshot
Topic: Conservation of Mass and Energy
Duration:
Grade Level: 7
9 days
Summary:
The following activities engage students in exploring the acidity or
alkalinity of substances (pH), through investigations involving pH
testing and analysis. Students will then use their knowledge of pH
values to analyze components of the natural world.
CLEAR LEARNING TARGETS
“I can”…statements
____ use the pH scale to compare and evaluate the acidity or alkalinity of a
compound
____measure pH values in the natural world (e.g. soil, water).
Activity Highlights and Suggested Timeframe
Day 1
Engagement: The objective of this activity is to engage students and formatively
assess their knowledge related to properties of acids and bases through a
discrepant event acid/base demonstration called the Witch’s Potion.
Day 2
Exploration: The objective of the following activity is to give students the
opportunity to work with and begin to develop a basic understanding of the
acidity or alkalinity of a substance through on-line simulation GIZMO: pH Analysis.
Days 3-4
Explanation: The objective of the following activity is to give students the
opportunity to develop their knowledge of pH scale values through close reading
and the CPO Lab Investigation 16B: Acids, Bases, and pH.
Days 5-7
Elaboration: The objective of the following activities is to give students the
opportunity to gain deeper understanding of pH values through close reading and
pH investigations involving substances in our natural world (e.g. water, soil).
Day 8 and ongoing
Day 9
Evaluation: Formative and summative assessments are used to focus on and
assess student knowledge and growth to gain evidence of student learning or
progress throughout the unit, and to become aware of students misconceptions
related to thermal energy transfer. A teacher-created short cycle assessment will
be administered at the end of the unit to assess all clear learning targets (Day 8).
Extension/Intervention: Based on the results of the short-cycle assessment, facilitate
extension and/or intervention activities.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
1
LESSON PLANS
NEW LEARNING STANDARDS:
7.PS.1 The properties of matter are determined by the arrangement of atoms.
Substances are classified according to their properties, such as metals and acids.
SCIENTIFIC INQUIRY and APPLICATION PRACTICES:
During the years of grades K-12, all students must use the following scientific inquiry and application practices with appropriate laboratory
safety techniques to construct their knowledge and understanding in all science content areas:
Asking questions (for science) and defining problems (for engineering) that guide scientific
investigations
Developing descriptions, models, explanations and predictions.
Planning and carrying out investigations
Constructing explanations (for science) and designing solutions (for engineering)that conclude
scientific investigations
Using appropriate mathematics, tools, and techniques to gather data/information, and analyze and
interpret data
Engaging in argument from evidence
Obtaining, evaluating, and communicating scientific procedures and explanations
*These practices are a combination of ODE Science Inquiry and Application and Frame-work for K-12 Science
Education Scientific and Engineering Practices
COMMON CORE STATE STANDARDS for LITERACY in SCIENCE:
*For more information: http://www.corestandards.org/assets/CCSSI_ELA%20Standards.pdf
CCSS.ELA-Literacy.RST.6-8.1 Cite specific textual evidence to support analysis of science and technical texts.
CCSS.ELA-Literacy.RST.6-8.2 Determine the central ideas or conclusions of a text; provide an accurate
summary of the text distinct from prior knowledge or opinions.
CCSS.ELA-Literacy.RST.6-8.3 Follow precisely a multistep procedure when carrying out experiments, taking
measurements, or performing technical tasks.
CCSS.ELA-Literacy.RST.6-8.4 Determine the meaning of symbols, key terms, and other domain-specific words
and phrases as they are used in a specific scientific or technical context relevant to grades 6–8 texts and
topics.
CCSS.ELA-Literacy.RST.6-8.9 Compare and contrast the information gained from experiments, simulations,
video, or multimedia sources with that gained from reading a text on the same topic.
STUDENT KNOWLEDGE:
Prior Concepts Related to Properties of Matter
PreK-2: Properties can be used to sort objects. Changes, including phase changes are explored.
Grades 3-5: Objects are composed of matter which has mass* and volume. Properties of solids, liquids and
gases are explored. Phase changes are reversible and do not change the identity of the material. The total
amount of matter and mass* remains the same when something changes.
Grade 6: All matter is made up of atoms that are in constant random motion. Elements, compounds and
molecules are introduced. The properties of solids, liquids and gases, and changes of phase are explained
by the motion and spacing of the particles.
Future Application of Concepts
High School: Metalloids and pH calculations are introduced. Mixtures are classified as homogenous or
heterogeneous. Trends in the properties and atomic structure of elements are related to the periodic table.
The role of valence electrons in reactivity is explored, balanced chemical equations are written and
stoichiometric problems are solved.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
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MATERIALS:
VOCABULARY:
Engage
5 500mL beakers or glasses
Vinegar and Ammonia
Phenolphthalein Indicator – provided by CCS
Science Department
Water
pH Analysis GIZMO Student Exploration Sheet
Page 1
Blue and Red Litmus Paper
Lemon Juice and Soap
Explore
Computers/Internet
GIZMO lesson materials and Student
Exploration Sheet
Explain
CPO Lab Investigation 16B Lab Materials
Elaborate
pH: A Balancing Act Student WS
Soil and Water samples
pH testing paper
pH in Our Natural World: Water and Soil
Student WS
Primary
Acidic
Acidity
Alkalinity
Basic
Neutral
pH
pH Scale
SAFETY
ADVANCED
PREPARATION
ENGAGE
(1 day)
(What will draw students into the
learning? How will you determine
what your students already know
about the topic? What can be
done at this point to identify and
address misconceptions? Where
can connections are made to
the real world?)
Columbus City Schools
Curriculum Leadership and Development
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Secondary
Indicator
Litmus Paper
Phenolphthalein
During testing and investigation of chemicals/substances, students should
wear safety glasses/goggles, and take other lab safety precautions.
If possible, reserve computers lab/laptops for www.explorelearning.com
GIZMO: pH Analysis.
Gather and prepare materials for witch’s potion demo and CPO
Investigation lab 16B.
Objective: The objective of this activity is to engage students and formatively
assess their knowledge related to properties of acids and bases
through a discrepant event demonstration.
What is the teacher doing?
What are the students doing?
THE WITCH’S POTION DEMO (Day 1)
PREPARATION: See Teacher
Information Sheet. The teacher
should set-up the
demonstration without
students seeing what is being
done. NOTE: Do not prepare
too far in advance, as the
liquids may evaporate causing
the demonstration to not work
properly. (5 minute maximum)
It is suggested that you
practice this demo before
showing to students.
The teacher chooses 4
volunteers to read the poem
and assist in the demo.
Ask students to hypothesize
what may have occurred to
cause the color changes.
THE WITCH’S POTION DEMO (Day 1)
1. 4 students are involved in assisting
during the teacher demonstration.
2. All students observe the
demonstration and hypothesize
what may have occurred to cause
the color changes.
3
Project the
www.explorelearning.com
GIZMO: pH Analysis on a
screen or SMARTboard.
If you are unfamiliar with
GIZMO’s or do not know your
username/password, see your
Math CCIT or call the CCS
science office @ x5297.
Distribute Page 1 of the pH
Analysis GIZMO Student
Exploration Sheet. Additional
lesson materials are available
on the
www.explorelearning.com
website.
Facilitate as students answer
and discuss prior knowledge
questions.
Small group activity or teacher
demonstration - Use blue and
red litmus paper to
demonstrate the use of an
indicator to determine if a
substance is an acid or base
by testing lemon juice and
soap.
-Lemon Juice is an acid and
will turn blue litmus to red.
-Soap is a base and will turn
red litmus to blue.
Facilitate the GIZMO Warm-up
as a class, and also test water
and vinegar.
Relate the pH of ammonia,
water and vinegar to the
witch’s potion demo.
Optional: Use litmus paper to
show that ammonia is a base,
and vinegar is an acid and
water is neutral.
3. Students complete prior knowledge
questions on the WS.
4. Students test lemon juice and soap
using litmus paper to determine if
the substance is an acid or base.
-This can also be a teacher
demonstration.
5. As a class, students work together
to learn how to use the GIZMO
through the GIZMO Warm-up.
-In addition to ammonia, also test
water and vinegar.
6. Relate the results of the tests to the
Witch’s Potion Demo.
7. Optional: Use litmus paper to show
that ammonia is a base, and
vinegar is an acid and water is
neutral.
8. Exit Ticket suggestion: Explain how
the witch’s potion worked, and
how it relates to acids, bases, and
indicators.
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Curriculum Leadership and Development
Science Department June 2013
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Objective: The objective of the following activity is to give students the
opportunity to work with and begin to develop a basic understanding
of the acidity or alkalinity of a substance through on-line simulation
GIZMO: pH Analysis
EXPLORE
(1 day)
(How will the concept be
developed? How is this relevant
to students’ lives? What can be
done at this point to identify and
address misconceptions?)
What is the teacher doing?
What are the students doing?
GIZMO: pH Analysis
www.explorelearning.com (Day 2)
Activity A & B can be
completed as a whole group
class instruction with teacher
facilitation or if possible,
students working individually or
partners on computers, laptops,
or IPads.
GIZMO: pH Analysis
www.explorelearning.com (Day 2)
1. Students work individually, with a
partner, or as a class to test various
substances to determine their pH
value.
-Complete Activity A & B
Additional lesson materials are
available on the
www.explorelearning.com
website.
If you are unfamiliar with
GIZMO’s or do not know your
username/password, see your
Math CCIT or call the CCS
science office @ x5297.
Follow-up with a class discussion
Objective: The objective of the following activity is to give students the
opportunity to develop their knowledge of pH scale values through
the CPO Lab Investigation: Acids, Bases, and pH.
EXPLAIN
(2 days)
(What products could the
students develop and share?
How will students share what they
have learned? What can be
done at this point to identify and
address misconceptions?)
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
What is the teacher doing?
What are the students doing?
CPO LAB INVESTIGATION 16B (Days 3-4)
Using the CPO textbook pp.
394-395, have students
compare the properties of
acids and bases.
Facilitate a close reading of
CPO textbook p. 397
NOTE: The discussion of hydroxide
CPO LAB INVESTIGATION 16B (Days 3-4)
1. Using the CPO textbook pp. 394-395,
compare the properties of acids and
bases.
and hydrogen ions as they relate to the
pH scale is reserved for high school and
will not be assessed at grade 7.
Facilitate CPO Lab Investigation
16.B.
2. Engage in a close reading of CPO
textbook p. 397.
3. Complete Lab Investigation 16B.
5
Objective: The objective of the following activities is to give students the
opportunity to gain deeper understanding of pH values through pH
investigations involving substances in our natural world.
ELABORATE
(3 days)
(How will the new knowledge be
reinforced, transferred to new
and unique situations, or
integrated with related
concepts?)
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
What is the teacher doing?
What are the students doing?
pH in our Natural World(Day 5)
pH in our Natural World (Day 5)
Facilitate a close reading of
CPO textbook pp. 398-399
and/or Show the
www.unitedstreaming.com
video clip: The pH in the
Chemistry of Nature [3:19]
1. Students engage in close reading of
CPO textbook pp. 398-399 and/or
watch the www.unitedstreaming.com
video clip: The pH in the Chemistry of
Nature [3:19]
Distribute the WS – pH: A
Balancing Act.
Split students into 4 groups and
facilitate a close reading on
pp. 402-403 in the CPO
textbook.
Facilitate the sharing of
answers.
2. Using the CPO Textbook pp. 402-403,
students either read the sections
aloud or silently.
3. Each group of students is assigned a
set of questions to answer using their
reading section and then present
their findings to the class.
4. All students are responsible for
summarizing the answer to each
question on their WS.
Administer a quick write in
student journals or on a
separate piece of paper:
“Summarize how pH plays an
important role in your body.”
5. Students perform a quick write
summarizing how pH plays an
important role in the body either in
journals, or on the back of their
paper.
What is the teacher doing?
What are the students doing?
pH in our Natural World: WATER (Day 6)
PREPARATION: Teacher collects
water samples from various
parts of the school (i.e. water
fountain, bathroom sink, fish
tanks, bottled water, etc.) or
asks students to gather the
water samples.
It is recommended that
students develop their own
investigation for testing the pH
of the water samples. However,
a lab sheet template has been
provided for those students that
need a more guided
experience: pH in Our Natural
World: WATER WS.
Teacher facilitates pH testing
and investigation.
OPTIONAL Extension: Test the
effects of water pH on an
Elodea plant (aquatic plant).
pH in our Natural World: WATER (Day 6)
1.
2.
Students gather water samples
from either home or different
parts of the school
yard/building
Students develop and
investigate the pH of the water
samples and complete lab
sheet.
6
What is the teacher doing?
What are the students doing?
pH in our Natural World: SOIL (Day7)
pH in our Natural World: SOIL (Day 7)
PREPARATION: Teacher collects
soil samples from various
sources, asks students to bring in
soil samples, or students gather
soil samples from around the
schoolyard. Include a fertilized
potting soil sample, as fertilizer is
a strong base.
Teacher facilitates the
gathering of soil samples and
students pH testing. NOTE: Use
distilled water to create soil
solutions.
It is recommended that
students develop their own
investigation for testing the pH
of the soils. However, a lab
sheet template has been
provided for those students that
need a more guided
experience: pH in Our Natural
World: SOIL WS
NOTE: Students will be
completing a similar lab using
outside water sources during
the Earth Science Unit.
1. Students gather soil samples
from either home or different
parts of the school yard.
2. Students develop an
investigation to test and
compare the pH of the soil
samples and complete a lab
report.
OPTIONAL Extension: Test the
effects of soil pH on plant
growth.
Objective: The objective of the assessments is to focus on and assess student
knowledge and growth to gain evidence of student learning or
progress throughout the lesson, and to become aware of students
misconceptions related to the alkalinity/acidity of substances and the
pH Scale.
EVALUATE
(on-going)
(What opportunities will students
have to express their thinking?
When will students reflect on
what they have learned? How
will you measure learning as it
occurs? What evidence of
student learning will you be
looking for and/or collecting?)
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
Formative
How will you measure learning as it occurs?
Consider developing a
teacher-created formative
assessment.
1. Student’s hypotheses based on the
Witch’s Potion Demo as well as priorknowledge/warm-up GIZMO
questions can be used to formatively
assess students’ prior knowledge of
acids and bases.
2. GIZMO and Lab 16B
questions/answers – These can be
used to assess the student’s ongoing
understanding of the pH scale.
Summative
What evidence of learning will demonstrate to
you that a student has met the learning
objectives?
1. pH in our Natural World Investigations
can be used to assess the students
ability to test and relate pH values to
various aspects of the natural world.
2. Teacher-created short cycle
assessment will assess all clear
learning targets (Day 8).
7
EXTENSION/
INTERVENTION
(1 day or as needed)
COMMON
MISCONCEPTIONS
EXTENSION
INTERVENTION
1. Test acids/bases of various strengths
1. www.unitedstreaming.com related
to determine rates of corrosion on
videos
metal pennies.
2. BBC KS3 Bitesize Interactive: Acids,
2. CPO Chapter Activity: Acid Rain and bases, and metals Stone Structures on CPO textbook p.
http://www.bbc.co.uk/bitesize/ks3/scie
404.
nce/chemical_material_behaviour/aci
3.GEO STAC: Acid Precipitation Lesson: ds_bases_metals/activity/
http://gis.lanecc.edu/geostac/tyser_f/
2. GEMS Alien Juice Bar acid-precipitation
http://scienceview.berkeley.edu/show
4. pH and plant growth/survival
case/flash/juicebar.html
investigation:
3. The pH Factor http://www.ncsu.edu/sciencejunction/ http://www.miamisci.org/ph/
depot/experiments/water/lessons/pH/
pHlesson2.htm
All acids are corrosive.
-Students can use litmus paper to test common foods to discover that
many of the things they eat are acids.
A base (alkalinity) is the opposite of an acid (acidity) and therefore not
harmful or corrosive.
-Bases have various strengths and can also be corrosive.
The acidity/alkalinity strength is based on how much of the substance is
present (e.g. the more substance there is, the stronger the
acidity/alkalinity.)
-pH is based on the chemical make-up of the substance, not the amount
there is.
Strategies to address misconceptions:
Misconceptions can be addressed through the use of Discovery Ed video clips,
and litmus/pH tests of various substances.
Lower-level: Consider partnering lower-level students with higher-level students
while working on GIZMO simulation or investigation activities;
Consider assigning specific substances for testing during
investigations; Consider performing a read-aloud during close
reading assignments.
Higher-Level: Consider providing opportunities for higher-level students to test
other substances that they may choose; Consider allowing students
to complete extension activities; Consider having students create
assessment questions for review.
DIFFERENTIATION
Strategies for meeting the needs of all learners including gifted students, English
Language Learners (ELL) and students with disabilities can be found at the
following sites:
ELL Learners:
http://www.ode.state.oh.us/GD/DocumentManagement/DocumentDownload.
aspx?DocumentID=105521
Gifted Learners:
http://www.ode.state.oh.us/GD/DocumentManagement/DocumentDownload.
aspx?DocumentID=105522
Students with Disabilities:
http://www.education.ohio.gov/GD/DocumentManagement/DocumentDownlo
ad.aspx?DocumentID=105523
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Curriculum Leadership and Development
Science Department June 2013
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Textbook Resources:
CPO Physical Science Textbook
Chapter 16.2: Acids, Bases, and pH pp. 394-406
CPO Lab Investigation 16B
ADDITIONAL
RESOURCES
Websites:
Phet Interactive Simulation: http://phet.colorado.edu/en/simulation/acidbase-solutions
Acid-base basics: http://www.chem4kids.com/files/react_acidbase.html
Acid-base chemistry: http://www.shodor.org/unchem/basic/ab/
Acids, bases:
http://www.files.chem.vt.edu/RVGS/ACT/notes/Notes_on_acids_and_bas
es.html
The pH scale: http://www.hbci.com/~wenonah/hydro/ph.htm
Natural indicators: http://www.pharmainfo.net/reviews/natural-phindicators-review,
http://antoine.frostburg.edu/chem/senese/101/acidbase/faq/householdindicators.shtml
Pickle science: http://ezinearticles.com/?Pickles---Science-in-YourKitchen&id=1051549
Discovery Ed (www.unitedstreaming.com):
Elements of Chemistry: Acids, Bases, and Salts [20:00]
Literature:
Brent, Lynette. (2009).Acids and Bases. Crabtree Pub.Co.
Baldwin, Carol. (2006). Acids & Bases. Raintree Publishers.
Oxlade, Chris. (2007). Acids and Bases. Heinemann Library.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
9
ENGAGE - THE WITCHES POTION DEMO
Teacher Info…
PREPARATION: Prepare the following without letting students see what you are doing.
However, do not prepare too far in advance, as the liquids may evaporate causing the
experiment to not go as planned.
Materials:
5 beakers (500 mL) or glasses
Container of water
Vinegar (Acid)
Ammonia (Base)
Phenolphthalein Indicator (turns pink in the presence of a base)
Eye droppers
Witch’s Potion Poem Sheet
1. Prepare 4 beakers or glasses and label them:
2. In #1 and #3 put 5 drops of phenolphthalein
3. In #2 and #4 put 5 drops of ammonia
(If you prepare these ahead of time, then be sure to stack them, one inside the other,
with an empty one inside the top one. This prevents your drops from evaporating.)
4. In #5 put 20 drops of vinegar.
5. Fill a large container with water.
5 drops
phenolpthalein
5 drops
ammonia
5 drops
phenolpthalein
5 drops
ammonia
20 drops
vinegar
BEAKER #1
BEAKER #2
BEAKER #3
BEAKER #4
BEAKER #5
6. Choose 4 volunteers to be the 4 witches. These students will read their sections of the
poem and do their section of the experiment.
Teacher Background: What is actually happening?
Phenolphthalein is a chemical indicator that turns pink in the presence of a base.
Therefore when beaker #1 is added to beaker #2 and beaker #3 is added to beaker
#4, the phenolphthalein reacts with the ammonia(base) and turns the solution bright
pink. When the phenolphthalein/ammonia solutions are added to beaker #5, the
ammonia (base) is neutralized by the vinegar (acid) and the solution turns clear again.
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Curriculum Leadership and Development
Science Department June 2013
10
The Witches Potion Poem – Teacher Information:
Teacher/Narrator: “Four witches made quite a commotion. When I invited
them to create a potion. Into four glasses went the magic brew...”
Experiment…Fill beakers #1-4 ¼ full with water.
5 drops
phenolpthalein
5 drops
ammonia
5 drops
phenolpthalein
5 drops
ammonia
20 drops
vinegar
BEAKER #1
BEAKER #2
BEAKER #3
BEAKER #4
BEAKER #5
Teacher/Narrator: "And into a rage the first witch flew: She shrieked,”
Witch #1: “There's no magic in this drink. To cast a
spell, it must be pink!"
Teacher/Narrator: “The second witch laughed,”
Witch #2: "The pink is here. Pour your brew in--the color
will appear!"
Experiment…Witch #1 pour water into the glass of Witch #2.
5 drops
phenolpthalein
5 drops
ammonia
BEAKER #1
BEAKER #2
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
5 drops
phenolpthalein
5 drops
ammonia
20 drops
vinegar
BEAKER #3
BEAKER #4
BEAKER #5
11
Teacher/Narrator: "The third witch shrieked,”
Witch #3: “We need more!”
Teacher/Narrator: “And gave her brew to Witch number Four."
Experiment…Witch #3 pour water into the glass of Witch #4.
BEAKER #1
5 drops
phenolpthalein
5 drops
phenolpthalein
5 drops
ammonia
5 drops
ammonia
BEAKER #2
BEAKER #3
BEAKER #4
20 drops
vinegar
BEAKER #5
Witch #4"Now there are two glasses of pink, But no one
asked me what I think! I'll invoke my powers to make it
clear. Be Gone Pink! Watch it disappear!"
Experiment…Pour both glasses with the pink solution into Beaker #5.
10 drops
phenolpthalein
10 drops
ammonia
20 drops
vinegar
BEAKER #1
BEAKER #2
BEAKER #3
BEAKER #4
BEAKER #5
4 Student Witch’s Sheet:
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
12
THE WITCHES POTION
Teacher/Narrator: "Four witches made quite a commotion. When I invited them
to create a potion. Into four glasses went the magic brew..."
Experiment…Fill each beaker ¼ full with water.
Teacher/Narrator: "And into a rage the first witch flew: She shrieked,”
Witch #1: “There's no magic in this drink. To cast a
spell, it must be pink!"
Teacher/Narrator: “The second witch laughed,”
Witch #2: "The pink is here. Pour your brew in--the color
will appear!"
Experiment…Witch #1 pour water into the glass of Witch #2.
Teacher/Narrator: "The third witch shrieked,”
Witch #3: “We need more!”
Teacher/Narrator: “And gave her brew to Witch number Four."
Experiment…Witch #3 pour water into the glass of Witch #4.
Witch #4:"Now there are two glasses of pink, But no one
asked me what I think! I'll invoke my powers to
make it clear. Be Gone Pink! Watch it
disappear!"
Experiment…Pour both glasses with the pink solution into the large container.
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Curriculum Leadership and Development
Science Department June 2013
13
Name: __________________________________Date: _____________________Period____________
Student Exploration: pH Analysis
www.explorelearning.com
Vocabulary: acid, acidic, alkaline, base, indicator, neutral, pH
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
1. Acids are substances that produce hydrogen ions (H+) when dissolved in water. Lemon juice is an
example of an acid.
A. What does lemon juice taste like? ________________________________________
B. What does it feel like if lemon juice gets in your eye? _________________________
2. Bases are substances that produce hydroxide ions (OH-) when dissolved in water. Hand soap is an
example of a base.
A. What does soap feel like? ______________________________________________
B. What does soap taste like? _____________________________________________
C. What does it feel like if soap gets in your eye? ______________________________
Gizmo Warm-up
The strength of an acid or base is measured on the pH scale. The term “pH” is
short for “potential of hydrogen.” It is a measure of how many excess H+ ions
there are in a solution. The pH scale runs from 0 to 14, with 0 representing the
highest concentration of hydrogen ions. Acidic substances have a pH below 7,
while alkaline substances (bases) have a pH above 7. Pure water has a pH of 7
and is considered neutral.
The pH Analysis Gizmo™ allows you to find the pH of a variety of liquids. In the
Gizmo, check that the Substance in the tube is Ammonia, and click Test. Wait
until the animation is finished.
1. Indicators change color in acids or bases. What is the color of the pH paper? ___________
2. Compare the paper to the pH color chart. What is the pH of ammonia? _____________
3. Is ammonia acidic or alkaline? _____________
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Name: __________________________________Date: _____________________Period____________
Get the Gizmo ready:
Activity A:
Click Reset.
Check that the 0-14 paper is selected.
Measuring pH
Goal: Find the pH of 18 common substances.
1. Test: Use the Gizmo to find the pH of each of the available substances. Classify each substance as acidic
(pH < 7), alkaline (ph > 7), or neutral (pH = 7).
0-14 pH indicator paper
Material in the tube
pH value
Acidic, alkaline, or neutral?
Baking soda
Bleach
Coffee
Cola
Drain cleaner
Hand soap
Juice (lemon)
Juice (orange)
Juice (tomato)
Milk
Milk of magnesia
Oven cleaner
Saliva (human)
Shampoo
Stomach acid
Vinegar
Water (distilled)
Water (ocean)
2. Summarize: Compare all the acidic substances and all the alkaline substances.
A. In general, what types of substances tend to be acidic? _______________________
___________________________________________________________________
B. What types of substances tend to be alkaline? ______________________________
___________________________________________________________________
Name: __________________________________Date: _____________________Period____________
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Curriculum Leadership and Development
Science Department June 2013
15
Get the Gizmo ready:
Activity B:
More accurate pH
Click Reset.
Select the 4.5-7.5 paper.
Goal: Find the pH of substances in a more accurate way.
1. Test: Before you begin testing with the 4.5-7.5 paper, list the pH values of the substances below that you
found using the 0-14 pH indicator paper. Then find the pH of each substance with the 4.5-7.5 paper.
4.5-7.5 pH indicator paper
Material in the tube
pH value (0 to 14 paper)
pH value (4.5 to 7.5 paper)
Coffee
Milk
Oven cleaner
Saliva (human)
Shampoo
Stomach acid
Water (distilled)
2. Analyze: Compare the pH values in each column.
A. How do these values compare? _________________________________________
___________________________________________________________________
B. What is an advantage of using the 4.5-7.5 paper? ___________________________
___________________________________________________________________
C. What is a disadvantage of using the 4.5-7.5 paper? __________________________
___________________________________________________________________
D. Given the results from two kinds of indicator paper, which substances appear to be neutral (pH =
7)? _____________________________________________________
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
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pH Analysis
Answer Key
Vocabulary: acid, acidic, alkaline, base, indicator, neutral, pH
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
[Note: The purpose of these questions is to activate prior knowledge and get students thinking. Students are
not expected to know the answers to the Prior Knowledge Questions.]
1. Acids are substances that produce hydrogen ions (H+) when dissolved in water. Lemon juice is an
example of an acid.
A. What does lemon juice taste like? Lemon juice has a sour taste.
B. What does it feel like if lemon juice gets in your eye? A burning sensation.
2. Bases are substances that produce hydroxide ions (OH-) when dissolved in water. Hand soap is an
example of a base.
A. What does soap feel like? Soap has a slippery texture.
B. What does soap taste like? Soap has a bitter taste.
C. What does it feel like if soap gets in your eye? A burning sensation.
Gizmo Warm-up
The strength of an acid or base is measured on the pH scale. The term “pH” is
short for “potential of hydrogen.” It is a measure of how many excess H+ ions
there are in a solution. The pH scale runs from 0 to 14, with 0 representing the
highest concentration of hydrogen ions. Acidic substances have a pH below 7,
while alkaline substances (bases) have a pH above 7. Pure water has a pH of 7
and is considered neutral.
The pH Analysis Gizmo™ allows you to find the pH of a variety of liquids. In the
Gizmo, check that the Substance in the tube is Ammonia, and click Test. Wait
until the animation is finished.
1. Indicators change color in acids or bases. What is the color of the pH paper? Dark green
2. Compare the paper to the pH color chart. What is the pH of ammonia? 11
3. Is ammonia acidic or alkaline? Alkaline
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
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Get the Gizmo ready:
Activity A:
Click Reset.
Check that the 0-14 paper is selected.
Measuring pH
Goal: Find the pH of 18 common substances.
1. Test: Use the Gizmo to find the pH of each of the available substances. Classify each substance as acidic
(pH < 7), alkaline (ph > 7), or neutral (pH = 7).
0-14 pH indicator paper
Material in the tube
pH value
Acidic, alkaline, or neutral?
Baking soda
8
Alkaline
Bleach
11
Alkaline
Coffee
5
Acidic
Cola
2 or 3
Acidic
Drain cleaner
13
Alkaline
Hand soap
9 or 10
Alkaline
Juice (lemon)
2 or 3
Acidic
Juice (orange)
3
Acidic
Juice (tomato)
4
Acidic
Milk
6 or 7
Acidic or neutral
Milk of magnesia
10
Alkaline
Oven cleaner
13 or 14
Alkaline
Saliva (human)
6 or 7
Acidic or neutral
Shampoo
6 or 7
Acidic or neutral
Stomach acid
1
Acidic
Vinegar
4
Acidic
Water (distilled)
6 or 7
Acidic or neutral
Water (ocean)
8
Alkaline
2. Summarize: Compare all the acidic substances and all the alkaline substances.
A. In general, what types of substances tend to be acidic?
Fruit juices and other beverages or food (cola, coffee, vinegar) tend to be acidic.
B. What types of substances tend to be alkaline?
Most of the alkaline substances are cleaners. These include hand soap, oven cleaner, bleach, and
drain cleaner.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
18
Get the Gizmo ready:
Activity B:
More accurate pH
Click Reset.
Select the 4.5-7.5 paper.
Goal: Find the pH of substances in a more accurate way.
1. Test: Before you begin testing with the 4.5-7.5 paper, list the pH values of the substances below that you
found using the 0-14 pH indicator paper. Then find the pH of each substance with the 4.5-7.5 paper.
4.5-7.5 pH indicator paper
Material in the tube
pH value (0 to 14 paper)
pH value (4.5 to 7.5 paper)
Coffee
5
5
Milk
6 or 7
6.5
Oven cleaner
13 or 14
7.5*
Saliva (human)
6 or 7
6.5
Shampoo
6 or 7
7
Stomach acid
1
4.5*
Water (distilled)
6 or 7
7
*Substances with a pH below 4.5 or above 7.5 cannot be measured accurately with the 4.5-7.5 indicator
paper.
2. Analyze: Compare the pH values in each column.
A. How do these values compare?
Most of the values are the same or nearly the same, but some are very different.
B. What is an advantage of using the 4.5-7.5 paper?
It gives a more accurate pH value for substances with a pH between 4.5 and 7.5.
C. What is a disadvantage of using the 4.5-7.5 paper?
The pH paper does not work for substances whose pH is not between 4.5 and 7.5.
D. Given the results from two kinds of indicator paper, which substances appear to be neutral (pH =
7)? Shampoo and distilled water appear to be neutral.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
19
Name_________________________________________Date________________Period_______________
pH: A Balancing Act
CPO Textbook pp.402-403
Directions: Using the CPO Textbook pp.402-403, read Acids, bases, and YOU as a class. Then,
read your assigned section of pH: A Balancing Act. Answer your assigned questions and
share your findings with the class.
Group 1: Imbalances
What is an acid-base balance?
What two organs regulate this
balance? How do they do this?
Group 2: Acidosis and its causes
What is acidosis?
What are some causes of
acidosis?
Group 3: Alkalosis and its causes
What is alkalosis?
What are some causes of
alkalosis?
Group 4: Balancing Act: food, drink,
exercise, calm, acid, base…
Is our body’s pH perfectly
neutral?
In what ways can our diet affect
the pH in our bodies?
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
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Name_________________________________________Date________________Period_______________
pH: A Balancing Act
CPO Textbook pp.402-403
TEACHER-KEY
Directions: Using the CPO Textbook pp.402-403, read Acids, bases, and YOU as a class. Then,
read your assigned section of pH: A Balancing Act. Answer your assigned questions and
share your findings with the class.
Group 1: Imbalances
What is an acid-base balance?
What two organs regulate this
balance? How do they do this?
Group 2: Acidosis and its causes
What is acidosis?
What are some causes of
acidosis?
An acid-base balance is the pH
balance that occurs within the human
body. A balance is required for our
organs and body to function properly.
Acidosis is a pH imbalance in which the
body has too much acid.
The two organs that regulate this
balance are:
1) Lungs: dispose of excess CO2
2) Kidneys: remove excess acid in our
blood and dispose of it as urine,
Group 3: Alkalosis and its causes
What is alkalosis?
What are some causes of
alkalosis?
Alkatosis is a pH imbalance in which the
body has too much base in the body’s
fluids.
Causes:
1) Hyperventilation
2) Altitude
3)Any disease that causes the bod to
lose too much CO2.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
Causes:
1) Lung Disease
2) Smoking
3) Diabetes
4)Severe Diarrhea
5)Heart/Liver Failure
6)Kidney Disease
7) Prolonged Exercise
Group 4: Balancing Act: food, drink,
exercise, calm, acid, base…
Is our body’s pH perfectly
neutral? What is the normal pH of
a healthy person?
In what ways can our diet affect
the pH in our bodies?
No,the body’s pH is slightly alkaline
(7.35-7.45)
Too much meat and not enough
veggies will cause pH to become too
acidic.
21
Name_______________________________________Date________________________Period_____
pH in Our Natural World: WATER
Guiding questions:
What is the pH of the water in the school?
Does all water have the same pH?
Hypotheses:
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
Procedures:
1) Gather water samples.
Water Test Site: _____________________________________________________________________
2) Dip pH strips in your water solution and leave submerged for at least 2 seconds.
Place your strips here. Observe color.
Compare your strips to the pH key to approximate the pH of your water sample.
Estimating to the nearest decimal, what is the pH? ______
3) Using graph paper, create a data table and record the results of all pH tests.
Develop a graph using your data to show the comparison between various water
samples and their pH levels.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
22
Name_______________________________________Date________________________Period_____
Post-lab questions:
1) Compare and contrast the pH values of the various samples. Summarize the results.
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
2) Were your hypotheses correct?
What is the average pH of the water in the school? ________________________________
__________________________________________________________________________________
__________________________________________________________________________________
Do all soils have the same pH? _______________
3) What factors can affect the pH of water? _________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
Extension
Guiding Question:
How does the pH of water affect aquatic plant growth and survival?
Develop an investigation that tests the growth of Elodea (an aquatic plant) in varying
pH levels to determine which water pH level is best growth and survival.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
23
Name_______________________________________Date________________________Period_____
pH in Our Natural World: WATER – TEACHER KEY
Guiding questions:
What is the pH of the water in the school?
Does all water have the same pH?
Hypotheses:
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
Answers Will Vary
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
Procedures:
1) Gather water samples.
Examples: Water Fountain, Bottled Water, Sink Water, Fish tank, etc.
Water Test Site: _____________________________________________________________________
2) Dip pH strips in your water solution and leave submerged for at least 2 seconds.
Place your strips here. Observe color.
Compare your strips to the pH key to approximate the pH of your water sample.
Answers Will Vary
Estimating to the nearest decimal, what is the pH? ______
3) Using graph paper, create a data table and record the results of all pH tests.
Develop a graph using your data to show the comparison between various water
samples and their pH levels.
Data will vary depending on samples
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
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Name_______________________________________Date________________________Period_____
Post-lab questions:
1) Compare and contrast the pH values of the various samples. Summarize the results.
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
Answers Will Vary
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
2) Were your hypotheses correct?
What is the average pH of the water in the school? ________________________________
__________________________________________________________________________________
Answers Will Depend on Location
__________________________________________________________________________________
No
Does all water have the same pH? _______________
3) What factors can affect the pH of water? _________________________________________
Filtration systems (Treatment plant); pipes, organisms in water, pollution, run-off,
__________________________________________________________________________________
soil composition through which water moves, etc.)
__________________________________________________________________________________
Extension
Guiding Question:
How does the pH of water affect aquatic plant growth and survival?
Develop an investigation that tests the growth of Elodea (an aquatic plant) in varying
pH levels to determine which water pH level is best growth and survival.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
25
Name_______________________________________Date________________________Period_____
pH in Our Natural World: SOIL
Guiding questions:
What is the pH of the soil around the school?
Do all soils have the same pH?
Hypotheses:
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
Procedures:
1) Gather soil samples.
Soil Test Site: _____________________________________________________________________
2) Create a soil solution by mixing your soil sample with distilled water.
3) Dip pH strips in your soil solution and leave submerged for at least 2 seconds.
Place your strips here. Observe color.
Compare your strips to the pH key to approximate the pH of your soil solution.
Estimating to the nearest decimal, what is the pH? ______
4) Using graph paper, create a data table and record the results of all pH tests.
Develop a graph using your data to show the comparison between various soils and
their pH levels.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
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Name_______________________________________Date________________________Period_____
Post-lab questions:
1) Compare and contrast the pH values of the various samples. Summarize the results.
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
2) Were your hypotheses correct?
What is the average pH of the soil around the school? ______________________________
__________________________________________________________________________________
__________________________________________________________________________________
Do all soils have the same pH? _______________
3) What factors can affect the pH of soil? ____________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
Extension
Guiding Questions:
Do you think all plants grow and survive in the same pH level soil?
Develop an investigation that tests the growth of a particular plant in soils with varying
pH levels to determine which soil is best for that particular plant.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
27
Name_______________________________________Date________________________Period_____
pH in Our Natural World: SOIL – Teacher Key
Guiding questions:
What is the pH of the soil around the school?
Do all soils have the same pH?
Hypotheses:
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
Answers Will Vary
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
Procedures:
1) Gather soil samples.
Examples: Soil near trees, Garden, Fertilized potting soil, Flower beds, Soil
under grassy area, Soil near road, etc.
Soil Test Site: _____________________________________________________________________
2) Create a soil solution by mixing your soil sample with distilled water.
3) Dip pH strips in your soil solution and leave submerged for at least 2 seconds.
Place your strips here. Observe color.
Compare your strips to the pH key to approximate the pH of your soil solution.
Answers Will Vary
Estimating to the nearest decimal, what is the pH? ______
4) Using graph paper, create a data table and record the results of all pH tests.
Develop a graph using your data to show the comparison between various soils and
their pH levels.
Data is dependent upon soil samples
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
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Name_______________________________________Date________________________Period_____
Post-lab questions:
1) Compare and contrast the pH values of the various samples. Summarize the results.
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
Answers Will Vary
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
__________________________________________________________________________________________
2) Were your hypotheses correct?
What is the average pH of the soil around the school? ______________________________
__________________________________________________________________________________
Answer Will Depend on Location
__________________________________________________________________________________
No
Do all soils have the same pH? _______________
3) What factors can affect the pH of soil? ____________________________________________
Soil Composition, Acid Rain/Pollution in Area, Fertilizer, Animals in the Area,
__________________________________________________________________________________
Vegetation, Soil forming factors, Rainfall and temperature,
__________________________________________________________________________________
Extension
Guiding Questions:
Do you think all plants grow and survive in the same pH level soil?
Develop an investigation that tests the growth of a particular plant in soils with varying
pH levels to determine which soil is best for that particular plant.
Columbus City Schools
Curriculum Leadership and Development
Science Department June 2013
29