I.
Grade Level/Unit Number:
9-12 Unit 13
II:
Unit Title:
Acids & Bases
III.
Unit Length:
5 days (on a 90 min. per day block schedule)
IV.
Major Learning Outcomes:
Students should be able to:












V.
Acids & Bases
Distinguish between acids and bases based on formula and chemical properties.
Distinguish between Arrhenius acids and bases and Bronsted-Lowry acids and
bases.
Compute concentration (molarity) of acids and bases in moles per liter.
Calculate molarity given mass of solute and volume of solution.
Calculate the mass of a solute needed to create a solution of a given molarity
and volume.
Solve dilution problems: M1V1=M2V2.
Differentiate between concentration (molarity) and strength (degree of
dissociation). No calculations involved.
Use pH scale to identify acids and bases.
Interpret pH scale in terms of the exponential nature of pH values in terms of
concentration.
Relate the color of an indicator to pH using pH ranges provided in a table.
Range should involve various values of pH (for example: 3.3 or 10.8).
Determine the concentration of an acid or base using titration. Interpret titration
curve for strong acid/strong base.
Compute pH, pOH, [H+], [OH-]. Calculations will involve only whole number
values (for example: pH or pOH values such as 3,5,8 and[H+] and [OH-] values
such as 1x10-4 or 1x10-10).
Content Objectives Includes (with RBT Tags):
Objective Objective
Number
5.04
Assess the physical and chemical properties of acids and
bases.
 General properties of acids and bases.
 Concentration and dilution of acids and bases.
 Ionization and the degree of dissociation (strengths)
of acids and bases.
 Indicators.
 Acid-base titration.
 pH and pOH.VSEPR theory.
Chemistry- Unit 13
DRAFT
RBT
Tag
B4
1
3.02
Apply the mole concept, Avogadro’s number and
conversion factors to chemical calculations:

Molarity of solutions.
VI.
English Language Development Objectives (ELD) Included:
NC English Language Proficiency (ELP) Standard 4 (2008) for Limited English
Proficiency Students (LEP)- English Language learners communicate information,
ideas, and concepts necessary for academic success in the content area of science.
Suggestions for modified instruction and scaffolding for LEP students and/or students
who need additional support are embedded in the unit plan and/or are added at the end
of the corresponding section of the lessons. The amount of scaffolding needed will
depend on the level of English proficiency of each LEP student. Therefore, novice level
students will need more support with the language needed to understand and
demonstrate the acquisition of concepts than intermediate or advanced students.
VII.
Materials/Equipment Needed
Activity
Household Acids * Bases
Materials
LabPro or CBL 2 interface
TI Graphing Calculator
DataMate program
pH Sensor
wash bottle
distilled water
ring stand
utility clamp
sensor soaking solution
Household solutions
Test tubes
Test tube racks
Red & blue litmus paper
Stirring rods
Red cabbage juice
250-mL beakers
VIII. Detailed Content Description:
Please see the detailed content description for each objective in the chemistry support
document. The link to this downloadable document is in the Chemistry Standard
Course of Study at:
http://www.ncpublicschools.org/curriculum/science/scos/2004/24chemistry
IX.
Unit Notes:
This unit is focused on the concept of the physical and chemical properties of acids and
bases. Students should be able to identify Arrhenius acids and bases and Bronsted-
Chemistry- Unit 13
DRAFT
2
Lowry acids and bases. They will be able to calculate the molarity of acids and bases
and solve dilution problems. Students will be able to differentiate between concentration
and strength of acids and bases. They will use the pH scale to identify acids and bases
and be able to calculate pH, pOH, [H+], and [OH-] of acidic and basic solutions.
Students will determine the concentration of acids and bases using titration and relate
indicator color change to pH. This unit is focused on the concept of the physical and
chemical properties of acids and bases.
In each unit, Goal 1 objectives which relate to the process of scientific investigation are
included. In each of the units, students will be practicing the processes of science:
observing, hypothesizing, collecting data, analyzing, and concluding. The Goal 1
Objectives are as follows:
COMPETENCY GOAL 1: The learner will develop abilities necessary to do and
understand scientific inquiry.
1.01 Design, conduct and analyze investigations to answer
questions related to chemistry.
 Identify questions and suggest hypotheses.
 Identify variables.
 Use a control when appropriate.
 Select and use appropriate measurement tools.
 Collect and organize data in tables, charts and
graphs.
 Analyze and interpret data.
 Explain observations.
 Make inferences and predictions.
 Explain the relationship between evidence and
explanation.
 Identify how scientists share findings.
Chemistry- Unit 13
DRAFT
This goal and these objectives
are an integral part of each of
the other goals. In order to
measure and investigate
scientific phenomena, students
must be given the opportunity to
design and conduct their own
investigations in a safe
laboratory. The students should
use questions and models to
formulate the relationship
identified in their investigations
and then report and share those
finding with others
Students will be able to:
 Identify questions and
suggest hypotheses.
 Identify variables.
 Use a control when
appropriate.
 Select and use appropriate
measurement tools.
 Collect and organize data in
tables, charts and graphs.
 Analyze and interpret data.
 Explain observations.
 Make inferences and
predictions.
 Use questions and models to
determine the relationships
3
between variables in
investigations.
 Identify how scientists share
findings.
If a teacher follows this curriculum (s)he will have addressed the goals and objectives of
the SCOS. However, teachers may want to substitute other activities that teach the
same concept. The unit length has extra time built in for quizzes, going over
homework, additional practice depending on the nature of the class, and
assessment. Teachers should utilize the textbook as a resource by assigning
homework each day and providing additional guided and independent practice.
Reference Tables:
The North Carolina Chemistry Reference Tables were developed to provide essential
information that should be used on a regular basis by students, therefore eliminating the
need for memorization. It is suggested that a copy be provided to each student on the
first day of instruction. A copy of the reference tables can be downloaded at the
following URL:
http://www.ncpublicschools.org/docs/curriculum/science/scos/2004/chemistry/referencet
ables.pdf
Essential Questions:
Essential questions for this unit are embedded within the unit. Essential questions are
those questions that lead to student understanding. Students should be able to answer
these questions at the end of an activity. Teachers are advised to put these questions
up in a prominent place in the classroom. The questions can be answered in a journal
format as a closure.
Safety: Students should wear chemical splash goggles during any lab activity involving
chemicals. This includes household substances. It is extremely important for the
safety and success of your students that you do ALL activities and labs prior to
assigning them to students. At the beginning of each lab, the teacher should address
any specific safety concerns relating to the activity.
Computer Based Activities:
Several of the recommended activities are computer based and require students to visit
various internet sites and view animations of various biological processes. These
animations require various players and plug-ins which may or may not already be
installed on your computers. Additionally some districts have firewalls that block
Chemistry- Unit 13
DRAFT
4
downloading these types of files. Before assigning these activities to students it is
essential for the teacher to try them on the computers that the students will use and to
consult with the technology or media specialist if there are issues. These animations
also have sound. Teachers may wish to provide headphones if possible.
X.
Global Content: Aligned with 21st Skills:
One of the goals of the unit plans is to provide strategies that will enable educators to
develop the 21st Century skills for their students. As much as students need to master
the NCSOS goals and objectives, they need to master the skills that develop problem
solving strategies, as well as the creativity and innovative thinking skills that have
become critical in today’s increasingly interconnected workforce and society. The
Partnership for 21st Century Skills website is provided below for more information about
the skills and resources related to the 21st Century classroom.
http://www.21stcenturyskills.org/index.php?option=com_content&task=view&id=27&Ite
mid=120
NC SCS
Chemistry
21st Century Skills
Communication Skills
1.01, 5.04 & Conveying thought or opinions effectively
3.02
1.01, 5.04 & When presenting information,
3.02
distinguishing between relevant and
irrelevant information
Activity

Household Acids *
Bases



Electronic Cereal
Oil & Water Don’t
Mix Lab
Design a Molecule
Project
Polarity Review
Electronic Cereal
Oil & Water Don’t
Mix Lab
Design a Molecule
Project
Polarity Review


Electronic Cereal
Oil & Water Don’t

1.01, 5.04 & Explaining a concept to others
3.02




Interviewing others or being interviewed
Computer Knowledge
1.01
Using word-processing and database
programs
1.01
Developing visual aides for presentations
1.01
Using a computer for communication
Learning new software programs
Employability Skills
1.01, 5.04 & Assuming responsibility for own learning
3.02
Chemistry- Unit 13
DRAFT
5
1.01, 5.04 & Persisting until job is completed
3.02
1.01, 5.04 & Working independently
3.02
Developing career interest/goals
1.01
Responding to criticism or questions
Information-retrieval Skills
Searching for information via the
computer
Searching for print information
Searching for information using
community members
Language Skills - Reading
5.04 & 3.02 Following written directions
Identifying cause and effect relationships
Summarizing main points after reading
Locating and choosing appropriate
reference materials
Reading for personal learning
Language Skill - Writing
Using language accurately
1.01, 5.04 & Organizing and relating ideas when
3.02
writing
Mix Lab
 Design a Molecule
Project
 Polarity Review
All activities
WIZARD assessment
questions
Most of the activities can
be presented as
opportunities for students
to follow written directions.
The teacher will have to
work with most students to
develop this skill over
time. The following
activities are well suited to
developing skills in
following directions:
 Electronic Cereal
 Oil & Water Don’t
Mix Lab
 Design a Molecule
Project
 Polarity Review


Chemistry- Unit 13
DRAFT
Oil & Water Don’t
Mix Lab
Design a Molecule
Project
6
1.01, 5.04 & Proofing and Editing
3.02
Synthesizing information from several
sources
Documenting sources
Developing an outline
Writing to persuade or justify a position
Creating memos, letters, other forms of
correspondence
Teamwork
1.01
Taking initiative
1.01, 5.04 & Working on a team
3.02
All activities




Thinking/Problem-Solving Skills
Identifying key problems or questions
1.01, 5.04 & Evaluating results
3.02



5.04 & 3.02
Developing strategies to address
problems




3.02
Developing an action plan or timeline

Electronic Cereal
Oil & Water Don’t
Mix Lab
Design a Molecule
Project
Polarity Review
Electronic Cereal
Oil & Water Don’t
Mix Lab
Design a Molecule
Project
Polarity Review
Electronic Cereal
Oil & Water Don’t
Mix Lab
Design a Molecule
Project
Design a Molecule
Project
EXPLORE: (60 minutes)
Chemistry- Unit 13
DRAFT
7
Household Acids and Bases Lab


Students will investigate various household acids and bases. They will use red
and blue litmus paper to determine if the substance is an acid or base, followed
by red cabbage juice to discover how indicators can show strengths. They will
complete the lab by using Vernier pH probes to determine the pH value.
Students will compare the various methods of experimentation.
If pH probes are not available, the teacher may substitute pHydrion paper for the
probeware.
Essential Question:
What is the relevance of common household acids and bases in regards to chemistry?
Household Acids and Bases
© 2008 Vernier Software & Technology
Many common household solutions contain acids and bases. Acid-base indicators, such
as litmus and red cabbage juice, turn different colors in acidic and basic solutions. They
can, therefore, be used to show if a solution is acidic or basic. An acid turns blue litmus
paper red, and a base turns red litmus paper blue. The acidity of a solution can be
expressed using the pH scale. Acidic solutions have pH values less than 7, basic
solutions have pH values greater than 7, and neutral solutions have a pH value equal to
7.
In this experiment, you will use litmus and a pH Sensor to determine the pH values of
household substances. After adding red cabbage juice to the same substances, you will
determine the different red cabbage juice indicator colors over the entire pH range.
Figure 1
Chemistry- Unit 13
DRAFT
8
MATERIALS
LabPro or CBL 2 interface
TI Graphing Calculator
DataMate program
pH Sensor
wash bottle
distilled water
ring stand
utility clamp
sensor soaking solution
household solutions
7 small test tubes
test-tube rack
red and blue litmus paper
paper towel
stirring rod
red cabbage juice
250-mL beaker
PROCEDURE
1. Obtain and wear goggles. CAUTION: Do not eat or drink in the laboratory.
Part I Litmus Tests
2. Label 7 test tubes with the numbers 1-7 and place them in a test-tube rack.
3. Measure 3 mL of vinegar into test tube #1. Refer to the data table and fill each of the
test tubes 2-7 to about the same level with its respective solution. CAUTION:
Ammonia solution is toxic. Its liquid and vapor are extremely irritating, especially to
eyes. Drain cleaner solution is corrosive. Handle these solutions with care. Do not
allow the solutions to contact your skin or clothing. Wear goggles at all times. Notify
your teacher immediately in the event of an accident.
4. Use a stirring rod to transfer one drop of vinegar to a small piece of blue litmus
paper on a paper towel. Transfer one drop to a piece of red litmus paper on a paper
towel. Record the results. Clean and dry the stirring rod each time.
5. Test solutions 2-7 using the same procedure. Be sure to clean and dry the stirring
rod each time.
Part II Red Cabbage Juice Indicator
6. After you have finished the Part I litmus tests, add 3 mL of red cabbage juice
indicator to each of the 7 test tubes. Record your observations. Dispose of the testtube contents as directed by your teacher.
Part III pH Tests
7. Prepare the pH Sensor for data collection.
a. Plug the pH Sensor into Channel 1 of the LabPro or CBL 2 interface. Use the link
cable to connect the TI Graphing Calculator to the interface. Firmly press in the
cable ends.
b. Remove the pH Sensor from the sensor storage solution bottle by unscrewing the
lid. Carefully remove the bottle, leaving the 0-ring and cap on the sensor body.
c. Rinse the tip of the sensor with distilled water and place the sensor tip into a
beaker containing sensor soaking solution. Use a utility clamp to fasten the pH
Sensor to a ring stand, as shown in Figure 1.
Chemistry- Unit 13
DRAFT
9
8. Turn on the calculator and start the DATAMATE program. Press
program.
CLEAR
to reset the
9. Set up the calculator and interface for the pH Sensor.
a. If the calculator displays pH in CH 1, proceed directly to Step 10. If it does not,
continue with this step to set up your sensor manually.
b. Select SETUP from the main screen.
c. Press ENTER to select CH 1.
d. Select PH from the SELECT SENSOR menu.
e. Select OK to return to the main screen.
10. Raise the pH Sensor from the sensor soaking solution and set the solution aside.
Use a wash bottle filled with distilled water to thoroughly rinse the pH Sensor. Catch
the rinse water in a 250-mL beaker.
11. Get one of the 7 solutions in the small container supplied by your teacher. Raise the
solution to the pH Sensor and swirl the solution about the sensor. When the pH
reading displayed on the main screen of the calculator stabilizes, record the pH
value (round to the nearest 0.01 pH unit).
12. Prepare the pH Sensor for reuse.
a. Rinse it with distilled water from a wash bottle.
b. Place the sensor into the sensor soaking solution and swirl the solution about the
sensor briefly.
c. Rinse with distilled water again.
13. Determine the pH of the other solutions using the Step 11 procedure. You must
clean the pH Sensor between tests, using the Step 12 procedure.
14. When you are done, rinse the sensor with distilled water and return it to the sensor
soaking solution. Select QUIT and exit the DATAMATE program..
PROCESSING THE DATA
1. Which of the household solutions tested are acids? How can you tell?
2. Which of the solutions are bases? How can you tell?
3. What color(s) is red cabbage juice indicator in acids? In bases?
4. Can red cabbage juice indicator be used to determine the strength of acids and
bases? Explain.
5. List advantages and disadvantages of litmus and red cabbage juice indicators.
DATA TABLE
Test
Tube
Solution
Chemistry- Unit 13
Blue
Litmus
DRAFT
Red
Litmus
Red Cabbage
Juice
10
pH
1
vinegar
2
ammonia
3
lemon juice
4
soft drink
5
drain cleaner
6
detergent
7
baking soda
EXPLAIN:
Students will share their observations and answers to the Household Acids & Bases lab
with the class. Instruct the students to provide reasons and explanations for their
answers.
ELABORATE:
Acid and Base PowerPoint (45 minutes)
The teacher should use the PowerPoint to introduce acid/base concepts including the
theories, pH scale, and how to calculate pH, pOH, [H3O+], and [OH-]. Guided practice is
provided.
Essential Question:
How are acids and bases identified according to their physical and chemical properties?
Language (ELP) Objectives for LEP Students:
 Complete filling notes handout with Acid and Base PowerPoint
(below).
Unit 13 Acids and Bases- Notes
1. List the properties of acids




______ to taste
React with some ________ to form _______ gas
Turns litmus paper ______
Phenolphthalein ______ __________
Chemistry- Unit 13
DRAFT
11


Electrolytes _____________
Form ________: hydronium ions ___________
2. List the properties of bases
 Bitter to __________
 Slippery to __________
 Turns litmus ___________
 Phenolphalein turns ____________
 Many form ______ (hydroxide ions) in ______
3. What is the difference between acidic, basic, and neutral solutions?



Acidic solutions: ____________________________
Basic solutions: _____________________________
Neutral solutions: ___________________________
4. Definitions of acids and bases
I. Arrhemius
Acids ____________ and bases ______________.
Ex.
II. Bronsted-Lowery
Acids are _________________ and bases are ___________
III. Conjugate acids and bases
A conjugate acid is _______________ and a conjugate base is
______________.
Ex.
A conjugate acid-base pair is two _____________ related by the
_______ or _______ of a single _______. Always _____________ with
an __________ and an _________.
Water is _________(a switch hitter?????) and can act as either
_________ or ________ depending _______________________ .
Monoprotic acids ________________________________________.
Ex.
Chemistry- Unit 13
DRAFT
12
Polyprotic acids _________________________________________ .
Ex.
5. Types of acids and bases
I. Strong _________ and _________: because electrolytes _________
100% in water
Ex.
II. Weak _______ and _______: because _____________ only
___________ ionize in water.
Ex.
Slide 1
Unit 13: Acids and Bases
Slide 2
Properties

Acids: Sour to taste
React with some metals to
form H2 gas
Turn litmus red
Phenolphthalein stays colorless
Electrolytes (conduct)
Form H+ (H3O+): hydronium ions
when attach to water molecule
Chemistry- Unit 13
DRAFT
13
Slide 3

Bases: Bitter to taste
Slippery to touch
Turn litmus blue
Phenolphthalein turns
MAGENTA!!!!!
Electrolytes
Many form OH- (hydroxide ions) in
water
Slide 4



Slide 5
Acidic solutions: more H3O+
Basic solutions: more OHNeutral solutions: [H3O+] = [OH-]
Definitions of acids and
bases
I. Arrhenius (traditional):
Acids: produce H3O+ in water
Bases: produce OH- in water
Ex: HCl(g)  H+(aq) + Cl-(aq)
NaOH(s)  Na+(aq) + OH-(aq)
**** most common definition used in
high school Chemistry!!!!!!!!!!

Slide 6

II. Brǿnsted-Lowry:
Acids: H+ donor (proton donor)
Bases: H+ acceptor (proton
acceptor)
Chemistry- Unit 13
DRAFT
14
Slide 7
Conjugate acid: particle formed
when a BASE gains a H+
(ex: NH3 NH4+)
base conj acid
Conjugate base: particle that remains after
an acid has donated a H+
(ex: H2O  OH-)
acid
conj base
Slide 8





Conjugate acid-base pair: two
substances related by the loss or gain
of a single H+……. Always paired with
acid and base……
Ex: NH3 + H2O  NH4+ + OHwhich is which?
Ex: HCl + H2O  H3O+ + Clhow about here?????
Slide 9






Water is AMPHOTERIC (a switch
hitter?????) can act as either an acid or
base depending on what it is coupled with
Monoprotic acids: donate only one H+
(ex: HClO4, HCl, HBr, HNO3)
Polyprotic acids: donate more than one H+
(ex: H2SO4, H2CO3)
**these actually ionize in steps, with
each H+ peeling away
Slide 10
Types of Acids and bases
I. Strong acids and bases: Strong
electrolytes because they ionize 100% in
water!!!!!!!
 Ex: strong acids: HCl, HNO3,H2SO4,
HClO4, HI, HBr
strong bases: (called ionic hydroxides)
NaOH, KOH, Ca(OH)2…. Do you notice
anything about the metals involved?????

Chemistry- Unit 13
DRAFT
15
Slide 11

II. Weak acids and bases: weak
electrolytes because they only
SLIGHTLY ionize in water!!!!!!!!!!!
ex: weak acids: H3PO4, HC2H3O2,
H2CO3
weak bases: low [OH-]
NH3 (NH4OH in water)
Slide 12
What in the world is pH?
Pouvoir hydrogene: “hydrogen power”
pH=measure of [H3O+]……. Acidity
+
 [H3O ] expressed in powers of 10
ex: 10-14 to 10-1
**Formula for calculation:
-log [H3O+] = pH


Slide 13




pH ranges from 0 to 14
pH <7  acids; 0 is strongest
pH = 7  neutral
pH >7  bases; 14 is strongest
Slide 14
Calculations for pH

Chemistry- Unit 13
if [H3O+] is:
a. 1.00 x 10-3M
b. 1.00 x 10-6M
c. 1.00 x 10-7M
DRAFT
16
Slide 15
Calculating pOH




pOH = -log [OH-]
pH + pOH = 14
So….. If pH is 2, then pOH is 12
If [OH-] is:
a. 1.0 x 10-5
b. 1.0 x 10-12
Slide 16
Calculating [H3O+] or [OH-]




If pH = 3, then [H3O+] is 1.0 x 10-3
If pOH = 5, then [OH-] is 1.0 x 10-5
Buffers: solutions that can absorb
moderate amounts of acids and bases
without a significant change in pH
**provide ions that react with excess
H3O+ or OH-
EVALUATE: (30 minutes)
Acid and Base Practice
This activity will allow students to elaborate on their understanding of pH, pOH, [H3O+],
and [OH-] calculations with guided and independent practice.
After students have completed these questions, the teacher will evaluate students’
understanding by going over the questions with the students.
ACID AND BASE PRACTICE
1. List 3 general properties of ACIDS.
2. List 3 general properties of BASES.
3. What are the two products of a neutralization reaction?
4. What are the proton-donor/proton-acceptor definitions of acids and bases? (i.e.
which is which?)
Chemistry- Unit 13
DRAFT
17
5. What ion is present in all acidic solutions?
6. How is pH related to the concentration of hydronium ions in solution?
7. What determines the degree to which an acid or base is weak or strong?
8. Are strong acids and bases good electrolytes? Explain why.
9. Explain how the concentration of an acid differs from the strength of an acid.
10. Of the five major types of reactions, which type is a neutralization reaction?
11. Circle the compound that is the proton donor:
HNO3 + H2O  H3O+ + NO3_
12. Name the acid and base that react to form KCl.
Acid: ________
Base: ________
13. Apples contain several acids, including malic acid, ascorbic acid (vitamin C), and
citric acid. What effect would apple juice have on phenolphthalein?
14. The desired pH range of chlorinated water in swimming pools is 7.2 to 7.8. How
does the concentration of hydronium ions in this solution compare to that of
lemon juice?
15. What is the pH of pure water?
16. To what subatomic particle is the hydrogen ion equivalent?
17. When a salt is formed, which forms the positive ion:
the acid or base? ______________
the negative ion, the acid or base? _____________
18. Water is formed from the reaction of an acid and a base. Why is it not classified
as a salt?
19. What is the formula for calculating pH mathematically?
20.Compare the pH values of acids, bases, and salts.
21. If you add HCl to Mg metal, what will you observe?
What products form from this reaction?
Chemistry- Unit 13
DRAFT
18
22.
Identify the following compounds as an acid, base, or salt.
a. LiOH ________________ b. H2CO3 ___________
c. Ba(OH)2 ______________ d. MgCl2 ___________
23. What happens when HNO3(aq) is added to KOH(aq)?
What are the products?
24. Circle the following compounds that can react with
H2SO4 to make a salt. Name the salt that would form
where applicable.
a. NaCl __________________
b. Ca(OH)2 ________________
c. HF ___________________
d. H2O __________________
e. Mg(OH)2 _______________
25.
A solution is an acid or a base and it doesn’t react with a
metal. Is its pH more likely to be 4 or 9? Why?
26.
Which of the following is a weak base?
NaCl
NH3
HCl
HF
KOH
27. Which of the following is a strong acid?
NH3
HC2H3O2 HCl
NaOH
28. An acid that only contains H and one other element is called a ____________
acid.
29. Any species that can react as either an acid or base is called
_________________.
30. Name the following acids:
a. HCl ________________ b. H2S _______________
c. HI ________________ d. HBr _______________
31. A solution is neutral if its [H3O+] = __________________
32. The pH scale range is ___________________________
33.
34.
In the space provided, identify each of the following substances as acidic,
basic, or neutral.
a. __________________ grapefruit
b. __________________ pure water
c. __________________ blood
d. __________________ soap
e. __________________ milk
Calcium and magnesium hydroxides are strong bases, but they are used as
antacids. Why won’t they harm human tissue?
Chemistry- Unit 13
DRAFT
19
35.
Write a balance equation for the neutralization reaction between KOH and
H2SO4.
36.
37.
What effect does an acid have on litmus?
Base on litmus?
How are binary acids named?
38.
What acid is used in car batteries?
39.
What acid is produced in the stomach?
40.
What acid is found in vinegar?
41.
Strong acids and strong bases are ______________ electrolytes.
42.
Hydroxides from which metallic group all form strong bases?
_________________
43. How do industrial processes cause acid rain?
ELABORATE:
Molarity of Acid and Bases PowerPoint (30 minutes)
Students need to understand the concept of concentration in solutions (molarity) and
the strength of acids and bases. The PowerPoint can be used to introduce these
concepts. Guided practice is also provided.
Essential Question:
How would you describe the difference between molarity and concentration in acids and
bases?
Slide 1
Molarity of acids and bases
Chemistry- Unit 13
DRAFT
20
Slide 2
Molarity (M):
number of moles of solute dissolved per
liter of solution
 M= moles solute
liters of solution
**** higher concentration: higher molarity
number
*** most common concentration unit in high
school chemistry

Slide 3



Sample: Calculate the molarity if 1.35 mol
H2SO4 is dissolved in 245mL of solution.
(5.51M)
Practice: What is the molarity if 92.4g of HCl
is dissolved in 2.0L of solution.
Practice: How many moles of solute are
contained in 125mL of 0.0500M Ba(OH)2?
(0.00625mol)
Dilutions (preparing molar
solutions)
Slide 4




M1V1=M2V2
(M1V1: molarity and volume of stock solution)
(M2V2: molarity of the dilute solution)
Sample: How many milliliters of a 5.0M H2SO4
stock solution would you need to prepare
100.0mL of
0.25M H2SO4?
(5.0mL)
Slide 5




Practice: If you dilute 20.0mL of a 3.5M
solution to make 100.0mL of solution, what is
the molarity of the dilute solution?
(0.70M)
How many milliliters of 2.55M NaOH is needed
to make 125mL of 0.75M solution?
(37mL)
Chemistry- Unit 13
DRAFT
21
Don’t confuse molarity and
strength of acid or base!!!
Slide 6
Molarity: concentration
Strength: degree of dissociation
Ex: strong acid with low concentration:
0.5M HCl
weak acid with high concentration:
12.0M HC2H3O2
EVALUATE: (45 minutes)
Molarity and Dilution Practice
This activity will allow students to elaborate on their understanding of molarity and
dilutions equations with guided and independent practice.
After students have completed these questions, the teacher will evaluate students’
understanding by going over the questions with the students.
The teacher should make sure that students understand where to find the equation in
the reference tables.
Essential Question:
How would you describe concentration of solutions in chemistry?
PRACTICE PROBLEMS: MOLARITY AND DILUTIONS
(Show your work for all problems. Do not forget units and sig figs!!!!)
Formulas:
Molarity (M) = Moles of solute
Liters of solution
M1V1=M2V2
1. Molarity is one of many ways to express ______________
of a solution. ( volume/mass/concentration/color)
2. A 100.5mL intravenous (IV) solution contains 5.10g of glucose (C6H12H6). What
is the molarity of this solution?
Chemistry- Unit 13
DRAFT
22
3. What is the molarity of an aqueous solution containing 40.0g of glucose in 1.5L
of solution?
4. What is the molarity of a bleach solution containing 9.6g of NaOCl per liter of
bleach?
5. Calculate the molarity of 1.60L of a solution containing 1.55g of dissolved KBr.
6. What volume of a 3.00M HCl stock solution would you use to make 0.300L of a
1.25M HCl solution?
7. How many milliliters of a 6.0M H2SO4 stock solution would you need to prepare
100.0mL of 0.25M H2SO4?
8. If you dilute 20.0mL of a 3.5M solution to make 100.0mL of solution, what is the
molarity of the dilute solution?
9. How many milliliters of 2.55M KOH is needed to make 125mL 1.25M KOH?
10. How many milliliters of 0.400M HBr solution can be made from 50.0mL of 8.00M
HBr?
ELABORATE: (45 minutes)
Neutralization Reactions PowerPoint
The teacher should use the PowerPoint to reintroduce equation writing relating it to
neutralization reactions. The teacher will lead into titration and model the calculations.
Guided practice is provided
Essential Question:
What are neutralization reactions?
Chemistry- Unit 13
DRAFT
23
Slide 1
Slide 2
Acid + base  salt + water
Salt is made of cation from base
and anion of acid
Mg(OH)2 + 2HCl  MgCl2 + H2O


Slide 3
Analytical method in which a standard
(known concentration) solution is used to
determine concentration of another
 **use an acid-base indicator…
 *** can determine where neutralization
occurs

Slide 4

Titration:
Chemistry- Unit 13
DRAFT
24
Slide 5





1. Buret is filled with standard solution and
other buret is filled with unknown
concentration solution.
2. Record initial volume of both burets (make
sure solution is to tip!)
3. Run some of the known solution into a
flask with indicator
4. Run unknown concentration sol’n until
there is a SLIGHT color change
***Remember the formula for MOLARITY!
Slide 6









1. 15.0cm3 of 0.5M NaOH and 25.0cm3 of vinegar of unknown
concentration are titrated. What is the molarity of the vinegar
solution?
NaOH + HC2H3O2  NaC2H3O2 + H2O
Is it balanced??????
15.0cm3 x 1L/1000cm3 x 0.5mol/1L =
0.00750 mol vinegar
Since all of the coefficients are 1, then moles NaOH = moles
vinegar
So….. 0.00750 mol NaOH = 0.00750 mol HC 2H3O2
0.00750 mol HC2H3O2 = 0.300M
0.025L
Slide 7



Now you try this one:
A 25mL solution of H2SO4 is completely
neutralized by 18mL of 1.0M NaOH using
phenolphthalein as the indicator. What is
the concentration of sulfuric acid?
(hint: write the balanced equation first and
check out ratio of H+ an OH-)
Slide 8





H2SO4 + 2NaOH Na2SO4 + 2H2O
0.018L NaOH x 1mol NaOH x 1mol H2SO4 =..0090mol H2SO4
1L
2mol NaOH
0.0090 mol H2SO4 = 0.36M H2SO4
0.025L
Chemistry- Unit 13
DRAFT
25
Slide 9
Titration curve of a strong base titrating a
strong acid
EXPLORE: (60 minutes)
Virtual Titration Lab
This activity can be done as a whole class or students may complete individually in a
computer lab. To access this activity, go to www.sasinschool.com. Log in, select
Chemistry, then Solutions, then Acid-Base Chemistry.
Essential Question:
How can the concentration of a solution be determined through titration?
Language (ELP) Objectives for LEP Students:
 In paragraph form, answer the above essential question and
summarize observations from the Virtual Titration Lab.
 Share verbally observations from Virtual Titration Lab.
EVALUATE:
Sample Assessment Questions for Unit 13
Unit
13
Goal/
RBT
Tag
5.04
C4
C4
Chemistry- Unit 13
Questions
1. What is the difference between solutions of a weak acid and a
strong acid?
a. the strong acid is more concentrated
b. the weak acid does not turn litmus red
c. the weak acid does not conduct electricity
d. the strong acid has more hydronium ions per liter
2. An acid base titration involves a
a. synthesis reaction
b. neutralization reaction
DRAFT
26
c. single replacement reaction
d. decomposition reaction
l
3.02
C4
1. What is the molarity of a solution that contains 125 g of NaCl in
4.00 L of solution?
a. 0.535 M
b. 2.14 M
c. 8.56 M
d. 31.3 M
2. How many milliliters of 18 M H2SO4 will be needed to make 500
mL of 1.5 M H2SO4?
a. 20.8 mL
b. 41.7 mL
c. 54.0 mL
d. 63.6 mL
EVALUATE: (45 minutes)
Below are sample test items obtained from the WIZARD test bank developed by
eduware™ that can be used to allow students to assess their understanding and
abilities and allow the teacher to evaluate the students understanding of key concepts
and skill development for this unit.
Chemistry- Unit 13
DRAFT
27
Chemistry- Unit 13
DRAFT
28
Chemistry- Unit 13
DRAFT
29
Chemistry- Unit 13
DRAFT
30