May/June 2017 – Vol. 29 No. 7

Acids and Bases Lab

Posted: Tuesday, February 1st, 2011

by Jeff Bradbury and Patricia Buchanan

Name ____________________

Date _____________________

Partners’ Name ____________

Question: When using materials to clean our house, are the products used usually acidic or basic, Why do you think so?

Purpose: To determine the importance of acids and bases while measuring the pH of different substances.

Part 1 Introduction:

In this lab you will be working in groups of two.

Acids were first recognized as substances that taste sour (The sour taste of lemons and limes is due to citric acid), will dissolve certain metals, and will dissolve some types of rocks.

Bases were characterized by their bitter taste and slippery feel (Hand soaps and toothpastes, for example).

A neutral solution is neither basic nor acidic.  Acids and bases will react together to form neutral solutions.  One can say that an acid will neutralize a base and vice-versa.

Indicators are substances that change color depending on whether they are in an acidic or basic solution.

In today’s lab you will observe some characteristic chemical and physical properties of acids and bases.


Safety goggles must be worn at all times. Hydrochloric acid, HCl, and acetic acid, HC2H3O2 can harm eyes, skin, and clothing.  Handle with care.  Any acid spilled on the skin or splashed into your eye should be rinsed with a large volume of water. NaOH and NH3(aq) solutions are corrosive to the skin and can harm your eyes.  Any base spilled on the skin or splashed into your eyes should be rinsed with a large volume of water.

Measuring pH with pH (Universal indicator) paper:

In your spot plate, obtain a sample (half-fill the wells) of each of the solutions shown in the table below.  Dip a small (1cm) piece of Universal Indicator paper into each well.  Record the color of the paper and match the color to the pH scale on the tube of paper.

Measuring pH with cabbage juice:

Make sure there is no Universal Indicator paper in the solution wells.  Obtain a piece of purple cabbage (one leaf) from the reagent bench.  Break it up into small pieces and boil it in about 150 ml of de-ionized water in a 250 ml beaker.  Add 15 drops of the cabbage juice extract to each of the wells of your spot plate.  Make sure you add the same amount of extract to each well.  Record the color of each solution.

Complete the table that compares the colors of each pH indicator at each pH

Table 1: Chemicals and their pH

Solution Color of cabbage juice Color of pH paper pH
.1 M HCL
.01 M HCl
.001 M HCl
.1 M NaOH
.01 M NaOH
.001 M NaOH
Orange Juice
Distilled water
Tap water
Lemon juice

Compare your results with others in your group. Re-test those that are different.

Dispose of all solutions into the sink.

Complete the table showing the color of cabbage juice at each pH. 1-14.

Cabbage juice color pH

Acid Base Notes

Properties of Acids and Bases
Chemistry of Acids and Bases

Questions and Answers:

1.       Which substances had different pH’s than you expected?

2.       Why are acids and bases important?

3.       Were the household cleaners basic or acidic or both?

4.       What does pH mean to you now?

Jeff Bradbury is a professor of chemistry at Cerritos College in Norwalk and is community college director for CSTA; Patricia Buchanan is the Cal Grip Grant Project Assistant at Cerritos College. The original idea for this activity came from the Los Angeles County Office of Education 15 years ago, which the authors modified.

Written by California Science Teachers Association

California Science Teachers Association

CSTA represents science educators statewide—in every science discipline at every grade level, Kindergarten through University.

Leave a Reply


Participate in Chemistry Education Research Study, Earn $500-800 Dollars!

Posted: Tuesday, May 9th, 2017

WestEd, a non-profit educational research agency, has been funded by the US Department of Education to test a new molecular modeling kit, Happy Atoms. Happy Atoms is an interactive chemistry learning experience that consists of a set of physical atoms that connect magnetically to form molecules, and an app that uses image recognition to identify the molecules that you create with the set. WestEd is conducting a study around the effectiveness of using Happy Atoms in the classroom, and we are looking for high school chemistry teachers in California to participate.

As part of the study, teachers will be randomly assigned to either the treatment group (who uses Happy Atoms) or the control group (who uses Happy Atoms at a later date). Teachers in the treatment group will be asked to use the Happy Atoms set in their classrooms for 5 lessons over the course of the fall 2017 semester. Students will complete pre- and post-assessments and surveys around their chemistry content knowledge and beliefs about learning chemistry. WestEd will provide access to all teacher materials, teacher training, and student materials needed to participate.

Participating teachers will receive a stipend of $500-800. You can read more information about the study here:

Please contact Rosanne Luu at or 650.381.6432 if you are interested in participating in this opportunity, or if you have any questions!

Written by California Science Teachers Association

California Science Teachers Association

CSTA represents science educators statewide—in every science discipline at every grade level, Kindergarten through University.

2018 Science Instructional Materials Adoption Reviewer Application

Posted: Monday, May 8th, 2017

The California Department of Education and State Board of Education are now accepting applications for reviewers for the 2018 Science Instructional Materials Adoption. The application deadline is 3:00 pm, July 21, 2017. The application is comprehensive, so don’t wait until the last minute to apply.

On Tuesday, May 9, 2017, State Superintendent Tom Torlakson forwarded this recruitment letter to county and district superintendents and charter school administrators.

Review panel members will evaluate instructional materials for use in kindergarten through grade eight, inclusive, that are aligned with the California Next Generation Science Content Standards for California Public Schools (CA NGSS). Learn More…

Written by California Science Teachers Association

California Science Teachers Association

CSTA represents science educators statewide—in every science discipline at every grade level, Kindergarten through University.

Lessons Learned from the NGSS Early Implementer Districts

Posted: Monday, May 8th, 2017

On March 31, 2017, Achieve released two documents examining some lessons learned from the California K-8 Early Implementation Initiative. The initiative began in August 2014 and was developed by the K-12 Alliance at WestEd, with close collaborative input on its design and objectives from the State Board of Education, the California Department of Education, and Achieve.

Eight (8) traditional school districts and two (2) charter management organizations were selected to participate in the initiative, becoming the first districts in California to implement the Next Generation Science Standards (NGSS). Those districts included Galt Joint Union Elementary, Kings Canyon Joint Unified, Lakeside Union, Oakland Unified, Palm Springs Unified, San Diego Unified, Tracy Joint Unified, Vista Unified, Aspire, and High Tech High.

To more closely examine some of the early successes and challenges experienced by the Early Implementer LEAs, Achieve interviewed nine of the ten participating districts and compiled that information into two resources, focusing primarily on professional learning and instructional materials. Learn More…

Written by California Science Teachers Association

California Science Teachers Association

CSTA represents science educators statewide—in every science discipline at every grade level, Kindergarten through University.

Using Online Simulations to Support the NGSS in Middle School Classrooms

Posted: Monday, May 8th, 2017

by Lesley Gates, Loren Nikkel, and Kambria Eastham

Middle school teachers in Kings Canyon Unified School District (KCUSD), a CA NGSS K-8 Early Implementation Initiative district, have been diligently working on transitioning to the Next Generation Science Standards (NGSS) integrated model for middle school. This year, the teachers focused on building their own knowledge of the Science and Engineering Practices (SEPs). They have been gathering and sharing ideas at monthly collaborative meetings as to how to make sure their students are not just learning about science but that they are actually doing science in their classrooms. Students should be planning and carrying out investigations to gather data for analysis in order to construct explanations. This is best done through hands-on lab experiments. Experimental work is such an important part of the learning of science and education research shows that students learn better and retain more when they are active through inquiry, investigation, and application. A Framework for K-12 Science Education (2011) notes, “…learning about science and engineering involves integration of the knowledge of scientific explanations (i.e., content knowledge) and the practices needed to engage in scientific inquiry and engineering design. Thus the framework seeks to illustrate how knowledge and practice must be intertwined in designing learning experiences in K-12 Science Education” (pg. 11).

Many middle school teachers in KCUSD are facing challenges as they begin implementing these student-driven, inquiry-based NGSS science experiences in their classrooms. First, many of the middle school classrooms at our K-8 school sites are not designed as science labs. Learn More…

Powered By DT Author Box

Written by NGSS Early Implementer

NGSS Early Implementer

In 2015 CSTA began to publish a series of articles written by teachers participating in the NGSS Early Implementation Initiative. This article was written by an educator(s) participating in the initiative. CSTA thanks them for their contributions and for sharing their experience with the science teaching community.

Celestial Highlights: May – July 2017

Posted: Monday, May 8th, 2017

May Through July 2017 with Web Resources for the Solar Eclipse of August 21, 2017

by Robert C. Victor. Twilight sky maps by Robert D. Miller. Graphs of planet rising and setting times by Jeffrey L. Hunt.

In spring and summer 2017, Jupiter is the most prominent “star” in the evening sky, and Venus, even brighter, rules the morning. By mid-June, Saturn rises at a convenient evening hour, allowing both giant planets to be viewed well in early evening until Jupiter sinks low in late September. The Moon is always a crescent in its monthly encounters with Venus, but is full whenever it appears near Jupiter or Saturn in the eastern evening sky opposite the Sun. (In 2017, Full Moon is near Jupiter in April, Saturn in June.) At intervals of 27-28 days thereafter, the Moon appears at a progressively earlier phase at each pairing with the outer planet until its final conjunction, with Moon a thin crescent, low in the west at dusk. You’ll see many beautiful events by just following the Moon’s wanderings at dusk and dawn in the three months leading up to the solar eclipse. Learn More…

Powered By DT Author Box

Written by Robert Victor

Robert Victor

Robert C. Victor was Staff Astronomer at Abrams Planetarium, Michigan State University. He is now retired and enjoys providing skywatching opportunities for school children in and around Palm Springs, CA. Robert is a member of CSTA.