Ms. Sameroff
Acids, Bases, and the pH Scale
I.
Time: 50 minutes
II.
Materials:
a. Handout: “Acids, Bases, and the pH Scale”
III.
Objectives:
After successful completion of the lesson, students will be able to:
a. SWBAT define and describe acids and bases
b. Explain how neutralization disassociation reactions relate to the formation and neutralization of
acids and bases.
Standards
HS-PS1-7. Use mathematical representations to support the claim that atoms, and therefore
mass, are conserved during a chemical reaction. [Clarification Statement: Emphasis is on using
mathematical ideas to communicate the proportional relationships between masses of atoms
in the reactants and the products, and the translation of these relationships to the macroscopic
scale using the mole as the conversion from the atomic to the macroscopic scale. Emphasis is
on assessing students’ use of mathematical thinking and not on memorization and rote
application of problem-solving techniques.] [Assessment Boundary: Assessment does not
include complex chemical reactions.]
HS-PS1-11. Plan and conduct an investigation to compare properties and behaviors of acids and
bases. [Clarification Statement: Examples of properties could include pH values (concentration),
neutralization capability and conductivity. Observations of behaviors could include the effects
on indicators, reactions with other substances, and efficacy in performing titrations.]
[Assessment Boundary: Reactions are limited to Arrhenius and Bronsted-Lowry acid-base
reactions.]
Opening: (5 minutes)
Students will look at a picture of acids and bases, then name
c. Development:
i. Pass out the handout “Acids, Bases, and the pH Scale”. Students will use the worksheet to fill
in the blanks (20 minutes).
IV.
V.
ii. Have students read the handout “Acids and Bases”
iii. Instruct them read the first page, color the molecules in each reaction, and then answer the
questions in groups of 2 or 3. (20 minutes)
iv. You may wish to review the questions as a class.
d. Closing: (5 minutes)
i. Give each student group a topic to summarize for the rest of the class. Assign the topics acid
properties, base properties, acid examples, base examples, ph Scale, and buffers.
Suggested Assessments:
a. Give examples of biological buffers/explain buffers and ask the students to explain how they work.
b.
c. Student completion of “Acids, Bases, and the pH Scale” handouts will assess the above objectives.
Related Links/Resources:
a. The handout “Acids and Bases” illustrates the basics of acids and bases and is a suggested student
activity for this lesson.