by Carolyn Holcroft

The Academic Senate for California Community Colleges (ASCCC) is a nonprofit organization that seeks to advance community college education in California. Title 5 of the California Code of Regulations grants the ASCCC authority to represent community college faculty to the California Board of Governors (BOG) and the Chancellor’s Office, serving as a unified faculty voice in matters of statewide concern. In keeping with this purpose, the ASCCC holds two plenary meetings each year. These provide community college faculty with opportunities to discuss issues facing California educators, and the meetings culminate in a formal resolution process to advise ASCCC leadership on how to represent CCC faculty to the BOG or Chancellor’s Office. (more…)

CSTA is pleased to announce the appointment of Carolyn Holcroft to the position of two-year college director. Carolyn is a biology professor at Foothill College in Los Altos Hills, CA. She holds a PhD in Molecular Genetics/Microbiology from the University of Kansas and a BSN from the University of Kansas Medical Center. In addition to her teaching responsibilities, Carolyn serves as an Academic Senate for the California Community Colleges (ASCCC) Statewide Curriculum Committee member.  Prior to Foothill College, Carolyn was an assistant professor at the University of Kansas School of Nursing. She worked for several years as a Level II RN in a neonatal intensive care unit. (more…)

by Marian Murphy-Shaw

As of this issue CSTA will have a new Two-Year College Board member – still TBA as I write this – who will bring the voice of California’s Community Colleges to the table whenever CSTA meets at a conference or board meeting. There a not many arenas in California education where K-12, Community College, and other higher education partners meet together, and I feel fortunate to be involved in more than one of them as part of my role in education. (more…)

by Jeff  Bradbury and Patricia Buchanan

Name ____________________

Date _____________________

Partner’s Name ____________

Question: The work of a crime scene investigator (CSI) is to identify certain found liquids or solids in an investigation, how could we find out the identity of an unknown substance?

Purpose: To learn how to classify matter and its changes.

Part 1 Introduction:

Background Information:

1) A pure substance is a sample of matter that has a definite, fixed composition, and the same properties throughout the sample.  Each pure substance has its own set of characteristic properties. (more…)

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.

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

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.

Acid Base Notes

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.

Name __________________

Date ___________________

Partners’ Names _________

by Jeff Bradbury and Patricia Buchanan

Question: Water is unique in that it is the only natural substance that is found in all three states: liquid, solid (ice), and gas (steam).  What are the molecular differences between each of the states? (more…)

by Jeff Bradbury and Patricia Buchanan

Question: All of these individual experiments found in this lab relate to one another. In knowing this, what one property of gases is demonstrated in the following experiments? (more…)

by Jeff Bradbury and Patricia Buchanan

Name ____________________

Date _____________________

Partner’s Name_____________

Question: Food provides us with energy to live, but how much of this energy can actually be found in a single peanut?

Purpose: To determine the heat of a chemical reaction.

Part 1 Introduction

Background Information:

1.       What is a calorie?

A Calorie is a unit of heat.  It is the amount of heat needed to raise the temperature of 1 gram of water 1 degree Celsius.  You will actually measure the calories of a food product and compare this to the calories on the container.  Food Calories usually have an upper case C.  1 Calorie = 1000 calories.  Today you will measure calories and then convert them to Calories.

2.       How are heat and temperature different?

Temperature is the average amount of kinetic energy contained in the molecules of a substance.  It is measured with a thermometer and the units are degrees Celsius.  Heat is the total amount of energy in a sample of substance.  It is measured indirectly and the units are calories.

3.       How is heat measured?

To measure calories in food, for example, the food is burned in a combustion chamber.  The heat from the combustion reaction of the food is used to raise the temperature of a sample of water.  Knowing the mass of the water and the temperature change of the water the heat gained by the water can be calculated using the following equation:

M X C X ΔT = Heat change in the water (q)

M is the mass of the water.  Δ T is the final temperature of the water—the initial temperature of the water (Δ T means change in temperature).  C is a constant called specific heat.  It tells how a particular substance absorbs heat.  All substances absorb heat differently.  It takes one calorie of heat to raise the temperature of one gram of water one degree Celsius.  C for water is 1 cal/g ^oC. (more…)