Electrolysis in the Classroom

Lesson objective:

Students will be able to demonstrate the process of electrolysis using common, household items.

Materials:

1 Nine-volt battery
1 Empty 35mm plastic film case with lid
1 Nine-volt battery clip with leads
2 Alligator clips attached to the leads
2 Small pencils with both ends sharpened
1 Acetate sheet, waxed paper, or petri dish
2 Drops of blue food coloring

Procedure:

Place the 9-volt battery in the empty 35mm film case.
Make two small holes in the lid of the case for the battery clip wires to go through.
Connect the battery clip to the battery and replace the plastic lid.
On an acetate sheet, piece of waxed paper, or petri dish, place several drops of water (A petri dish filled with water works well, if placed on an overhead projector. More students can observe).
Connect the alligator clips to one end of each pencil. Make sure both ends of the pencils are sharpened to a fine point.
Place the other sharpened ends of the pencils in the water. Bubbles of gas may come from the ends of the pencils in the water. These are bubbles of oxygen gas and hydrogen gas.
Place a sheet of white paper under the acetate sheet
Place 20 drops of water on the acetate sheet. Dissolve several crystals of table salt (sodium chloride) in the water. A toothpick may be used to mix the salt in the water.
Place two drops of blue food coloring in the salt solution and mix.
Place the two sharpened ends of the pencil in the solution.
Gas bubbles form at the end of one of the pencils which causes the blue food coloring to fade and finally become colorless. This is chlorine gas. After a short period, one can detect the aroma of the gas.

An electrolysis apparatus from a supply company may cost about $100. It may require thirty volts of electricity and the students must watch while the instructor performs the experiment. The procedure above is an inexpensive way to show the process. The equipment costs about $1.35, and the students get to do the work!

Jack Young, Chemistry teacher, Columbus East High School, Columbus, IN

This document was last updated 7/5/97 by Chandra Hawley.
Copyright1996 Indiana University - Center for Adolescent Studies, all rights reserved.
Kris Bosworth - Director
don't try to take it all on myself. I help them identify options, or refer them to a counselor.

Teacher Talk How do you establish high expectations for your students?

Mr. Moore: I tell them they all start out the semester with A's and can do "A" work - a "C" is not good enough. I explain to them that outside of school you would not put up with "C" work, so why do so in school? For example, would you want a tax auditor doing"C" work on your tax reports? or an airline pilot, or a surgeon? Too often we focus on failure instead of success.

Teacher Talk: Any other tips for our new teachers?

Mr. Moore: Ask veteran teachers about teaching and discipline strategies. They may have some excellent tips.

Mr. Moore can be reached at 9100 Keystone Crossing, Suite 390,Indianapolis, IN 46240

Return to top of article

Making Content Relevant

Verna DeLuce is an English teacher at Tri-North Middle School, a 17-year veteran of the field with ten years in the middle schools.

A key to hooking the students is to relate the content to their lives. Personal connections to the subject matter need to be found, instead of teaching content without the kids in mind-we are building kids, not refrigerators! For example, when looking where things went wrong in U.S. History, the connections with today can be made; we are still vulnerable to these mistakes.

At Tri-North, we teach an 8th-grade humanities approach to English, including social studies, math, and other areas. We pool our teaching resources and help students to reflect on some basic questions they need to understand, such as"What does our country stand for?" We have students examine symbols which represent America (i.e. the Statue of Liberty and the bald eagle) and then create their own symbol which they feel is representative of America.

There must be a sense of reality in what they are studying, where we say "This is important" because there are implications for their future employment. They have to learn these kinds of things in order to succeed as life-long learners.

The students need to have something they enjoy too. I try to get the kids to read each evening and have some positive experiences reading what they want. We are journaling as well. This affords students the opportunity to interact with a book, to question, respond, disagree, or celebrate.

Assessment

I utilize portfolio assessment, which allows me greater flexibility in structuring my classes. For example, my students create portfolios and assess them at the end of each semester so they see their own growth.

Classroom Management

Extend yourself and they will know it. If you just shout to stay in control, it doesn't help. Teachers have to be respectful toward students, and leave sarcasm out. Also, I tell my students how hard I work and I try to get papers back within a week. I have high expectations for all my students. Bad papers are not acceptable, so I allow them to make revisions until they are done right. It takes a lot of effort to be an effective teacher, yet being able to make a positive impact on students' lives makes it all worthwhile.

Ms. DeLuce can be reached at Tri-North Middle School, 1000 W. 15th St., Bloomington, IN 47404

Return to top of article

Using Democracy in the Classroom

Barbara Brodhagen has been teaching language arts and social studies at the middle school level since 1980. She and another teacher facilitate student-directed learning with a class of 50-60 students.

In our classroom, there are three principles which guide us in our work together: maintaining dignity, honoring diversity, and democracy. To operationalize these ideas, we build our curriculum around questions kids have about themselves and their world. This approach empowers them to find answers to their own questions and presents a very different classroom atmosphere where students direct their own learning.

At the start of the year, we ask the students, "We will be working together for a year. How can we get to know each other?" Students decide on the activities and we do them. For example, one class wanted to do a survey of each other's interests, which led to an exploration of how to make a survey. So their ideas are translated into classroom learning. Then students begin to think of the questions they have about themselves and the world, and the class identifies the common ones. A committee of students goes through the lists and tries to find themes which connect the questions. Eventually, the students vote on them and pick the first theme (i.e. the environment or conflict).

Another committee is formed to find the original questions which fit under this theme "environment". Later the class works together to brainstorm for activities to answer their questions. The students then go through a process of deciding on activities, re-identifying questions they have (or changing them), and actually planning out the activities. Students find this very engaging. After an activity, we go back to the initial questions and ask, "How are we doing?"

The entire school day is not devoted to this at first, as it would be too much, so we do work on other things. The point is students are involved in a process where classroom learning is student-directed and democratic. We also allow for re-evaluating of the questions, themes, and activities.

Return to top of article

This document was last updated 5/30/97 by Chandra Hawley.
Copyright