May/June 2017 – Vol. 29 No. 7

Energy in Chemical Reactions Lab

Posted: Friday, October 1st, 2010

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.


125 grams of water are heated by burning a sample of sugar.  The temperature of the water goes from 21 oC to 76 oC.  How much heat did the water absorb?  How much heat did the sugar release?

Answer Absorbed:____________________ Released: ____________________


Safety goggles must be worn at all times.  Be careful when lighting a burner.

Part 2 Procedure

Procedure, Observations, and Data:

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

1. Measure the mass of the apparatus, which is a wire that is attached to a cork

2. Place 1/2 of a peanut on the apparatus and find the mass.

3. Put exactly 25 ml of water in a 100 ml beaker.  Measure and record the temperature of the water.

4. Light the peanut on fire with a Bunsen burner, and once the peanut is lit, quickly hold the beaker of water over the peanut.  The goal is to get as much heat into the water as possible.  (Is it possible to get all of the heat into the water?)

5. Do not let the water boil!  Blow out the flame before this happens.

6. After the peanut has burned, make sure the water is mixed so that the hot water is evenly dispersed in the beaker, and measure the temperature of the water and record.

7. Record the mass of the apparatus and peanut after it was burned.  Be sure to pick up any crumbs that fell off of the wire.

8. Repeat this experiment until you have burned two peanuts.

Table 1:  Mass and Temperature Changes in a Chemical Reaction

Mass of apparatus Mass of apparatus and peanut (initial) Mass of apparatus and peanut (final) Temperature of water (initial) Temperature of water (final) Mass of water used

Part 3 Calculations (Do this for each peanut)

Show all of the calculations for one nut in your lab book but show the results of all calculations in a table in your book

1. What is the initial mass of the peanut?

2. What is the final mass of the peanut?

3. What is the change in mass of the peanut?

4. What is the change in temperature of the water?

5. What is the heat gain of the water in calories?

6. What is the heat gain of the water in Calories?

7. What is the experimental heat loss of the peanut in Calories?

8. What is the heat loss per gram of the peanut?

9. What is the average heat loss per gram of the peanut?

10. What is the theoretical heat loss per gram of the peanut in Calories? (from the average)

11. What is the efficiency of this experiment? (from the average)

Table 2:  Calculating Heat Changes in a Chemical Reaction

Initial mass of peanut Final mass of peanut Change in mass of peanut Change in temp. of water Heat gain of water cal. Heat gain of water Cal. Experimental heat loss of peanut in Cal. Experimental heat loss per gram of peanut in Cal. Ave. heat loss of peanut Theo. heat loss of peanut % Eff.


1. How could you make it so that more of the heat from the burning peanut goes into the water

2. The mass of the peanut went down and the temperature of the water went up.  Did you change matter into energy?  Make sure you explain your answer with evidence.

3. What happened to the matter of the peanut that was burned?

4. How did the energy get into the peanut in the first place?

Jeff Bradbury is a Professor of Chemistry at Cerritos College in Norwalk; 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.

One Response

  1. As a chemistry teacher of 30 years I have to say that with the number of students who have peanut allergies these days this lab has been modified by most of us to use other food sources from cheerios to cheetos but ANYTHING except NUTS
    If a kid is allergic and inhales the smoke from the peanut he will end in the hospital
    The questions on this lab are well thought out but PLEASE change the food source!
    It can also be done simply and easily with candles as the FUEL if you are not talking food energy but rather alternative fuels along with ethanol–just a few drops in a dish.
    I use an aluminum can to hold over the flame with a ring stand adn can even build an insulating chinmey

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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…

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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…

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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.