March/April 2017 – Vol. 29 No. 6

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.

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California Science Curriculum Framework Now Available

Posted: Tuesday, March 14th, 2017

The pre-publication version of the new California Science Curriculum Framework is now available for download. This publication incorporates all the edits that were approved by the State Board of Education in November 2016 and was many months in the making. Our sincere thanks to the dozens of CSTA members were involved in its development. Our appreciation is also extended to the California Department of Education, the State Board of Education, the Instructional Quality Commission, and the Science Curriculum Framework and Evaluation Criteria Committee and their staff for their hard work and dedication to produce this document and for their commitment to the public input process. To the many writers and contributors to the Framework CSTA thanks you for your many hours of work to produce a world-class document.

For tips on how to approach this document see our article from December 2016: California Has Adopted a New Science Curriculum Framework – Now What …? If you would like to learn more about the Framework, consider participating in one of the Framework Launch events (a.k.a. Rollout #4) scheduled throughout 2017.

The final publication version (formatted for printing) will be available in July 2017. This document will not be available in printed format, only electronically.

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.

Call for CSTA Awards Nominations

Posted: Monday, March 13th, 2017

The 2017 Award Season is now open! One of the benefits of being a CSTA member is your eligibility for awards as well as your eligibility to nominate someone for an award. CSTA offers several awards and members may nominate individuals and organizations for the Future Science Teacher Award, the prestigious Margaret Nicholson Distinguished Service Award, and the CSTA Distinguished Contributions Award (organizational award). May 9, 2017 is the deadline for nominations for these awards. CSTA believes that the importance of science education cannot be overstated. Given the essential presence of the sciences in understanding the past and planning for the future, science education remains, and will increasingly be one of the most important disciplines in education. CSTA is committed to recognizing and encouraging excellence in science teaching through the presentation of awards to science educators and organizations who have made outstanding contributions in science education in the state and who are poised to continue the momentum of providing high quality, relevant science education into the future. 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.

Call for Volunteers – CSTA Committees

Posted: Monday, March 13th, 2017


CSTA is now accepting applications from regular, preservice, and retired members to serve on our volunteer committees! CSTA’s all-volunteer board of directors invites you to consider maximizing your member experience by volunteering for CSTA. CSTA committee service offers you the opportunity to share your expertise, learn a new skill, or do something you love to do but never have the opportunity to do in your regular day. CSTA committee volunteers do some pretty amazing things: 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.

A Friend in CA Science Education Now at CSTA Region 1 Science Center

Posted: Monday, March 13th, 2017

by Marian Murphy-Shaw

If you attended an NGSS Rollout phase 1-3 or CDE workshops at CSTA’s annual conference you may recall hearing from Chris Breazeale when he was working with the CDE. Chris has relocated professionally, with his passion for science education, and is now the Executive Director at the Explorit Science Center, a hands-on exploration museum featuring interactive STEM exhibits located at the beautiful Mace Ranch, 3141 5th St. in Davis, CA. Visitors can “think it, try it, and explorit” with a variety of displays that allow visitors to “do science.” To preview the museum, or schedule a classroom visit, see Learn More…

Written by Marian Murphy-Shaw

Marian Murphy-Shaw

Marian Murphy-Shaw is the student services director at Siskiyou County Office of Education and is CSTA’s Region 1 Director and chair of CSTA’s Policy Committee.

Learning to Teach in 3D

Posted: Monday, March 13th, 2017

by Joseph Calmer

Probably like you, NGSS has been at the forefront of many department meetings, lunch conversations, and solitary lesson planning sessions. Despite reading the original NRC Framework, the Ca Draft Frameworks, and many CSTA writings, I am still left with the question: “what does it actually mean for my classroom?”

I had an eye-opening experience that helped me with that question. It came out of a conversation that I had with a student teacher. It turns out that I’ve found the secret to learning how to teach with NGSS: I need to engage in dialogue about teaching with novice teachers. I’ve had the pleasure of teaching science in some capacity for 12 years. During that time pedagogy and student learning become sort of a “hidden curriculum.” It is difficult to plan a lesson for the hidden curriculum; the best way is to just have two or more professionals talk and see what emerges. I was surprised it took me so long to realize this epiphany. Learn More…

Written by Guest Contributor

From time to time CSTA receives contributions from guest contributors. The opinions and views expressed by these contributors are not necessarily those of CSTA. By publishing these articles CSTA does not make any endorsements or statements of support of the author or their contribution, either explicit or implicit. All links to outside sources are subject to CSTA’s Disclaimer Policy: