Hands-On Chemistry: Safe enough for elementary school but robust enough for high school/college

• Jodye Selco*, Cal. Poly. Pomona jiselco@csupomona.edu

• Mary Bruno, Kordyak Elem. School, Rialto USD mbruno@rialto.k12.ca.us

• Sue Chan, Kolb Middle School, Rialto USD schan@rialto.k12.ca.us

Standards• 2-PS1.B Different kinds of matter exist and many of

them can be either solid or liquid, depending on temperature. Matter can be described and classified by its observable properties.

• 5th: PS1-B (Chemical Reactions)• MS-PS1-A (Structure and Properties of Matter) and

MS-PS1–B (Chemical Reactions)• HS-PS1-B (Chemical Reactions) • Cause and Effect, Planning and Carrying Out

Investigations, Analyzing and Interpreting Data, Communicating Results

Design Challenge• Having both teachers and students actually

“doing” real chemistry.

• Safe enough to use in portable classrooms in elementary schools (even in trailers!)

• Use of plastic (glass not allowed at elementary schools)

• Chemicals are safe and readily available

• Inexpensive

• Hands-on Inquiry

What we did:

• Devise a “mix and match” experiment where any ingredient could be mixed with another

• All powders are labeled A-F and liquids are labeled 1-6

• Used only “household” chemicals

• Include endothermic and exothermic reactions, color changes, gas evolution, …

Directions to Students• To ensure students understand

directions, they are provided via “Silent Demonstration” – pantomimed directions

• 1 tsp each two different powders added to sandwich Ziploc bag along with ½ oz liquid in condiment cup

• Squeeze out air, zip, mix, record

•Your Turn

Next Step• Asked to do 10 reactions as a group

• Share all data gathered in class to generate a testable question (e.g. when A+C are used, does it always turn purple?)

• Then student groups are asked to design an experiment that enables them to answer their own question

• Student groups then determine the answers to their own questions.

What happens?• Students get very excited

• Even weeks later, students remember their testable question, how they tested it, and what they found

• Students want to know what was used so they can do more at home (and whether they can do this at home)

• Students that do the hands-on labs can easily answer the benchmark questions.

5th Grade Science CST Scores

Factor of 4.4 increase in number of students that are proficient and advanced from 2004 to 2011. Chemistry professional development provided to teachers in 2005.

8th Grade Physical Science CST Scores

Factor of ~3 increase in number of students that are proficient and advanced from 2006 to 2011.

First 5th grade cohort in 8th grade 2007-2008.

High School Chemistry CST Scores

Factor of ~2.7 increase in number of students that are proficient and advanced from 2006 to 2011.

First 5th grade cohort in HS grade 2010 and 2011.

Ingredients used in this experiment.Powders LiquidsEpsom Salts Vinegar and red cabbage

juice

Baking Soda Water and red cabbage juice

Calcium Chloride Anhydride

Lemon juice and red cabbage juice

Powdered Lemonade Baking soda solution and red cabbage juice

Washing Soda (sodium carbonate)

Washing soda solution and red cabbage juice

Corn Starch Diluted tincture of iodine

Acknowledgements:

• Mary Bruno and Sue Chan• Rialto Unified School District 5th

grade teachers and students• Dr. Ed D’Souza for having the

wisdom to make us a teaching team

• CaMSP (California Mathematics and Science Partnership) grant

Thank You!

• Jodye Selco Ph.D. - Cal Poly Pomona• jiselco@csupomona.edu

• Lessons are posted at: http://www.csupomona.edu/~cemast/LessonPlan&Links.shtml

District Benchmark Exam

• A chemical reaction forms new products with different properties. Which of the following is a chemical reaction?

• A. Iron turning into rust. (62%, 52%)*

• B. Salt dissolving in water. (20%, 23%)

• C. Water freezing into ice cubes. (13%, 15%)

• D. A glass bowl breaking into many pieces. (5%, 10%)

• Use the table below to answer the question. • Reactions of Kitchen Substances with Water, Vinegar, and Iodine

• You have an unlabeled jar of baking soda and an unlabeled jar of salt. You could figure out what is in each jar by mixing each substance with ___________.

• iodine (6%, 13%) • sugar (13%, 14%) • vinegar (62%, 50%)* • water (20%, 29%)

Substance Water Vinegar Iodine

Sugar Dissolves, forming clear solution

Dissolves forming clear solution

No reaction

Salt Dissolves, forming clear solution

Dissolves forming clear solution

No reaction

Baking Soda Dissolves forming clear solution

Forms bubbles No reaction

• You have the following chemicals: 6 liquids labeled 1-6 and 6 powders labeled A-F. You combine two powders and one liquid in a Ziploc bag, mix and record your observations. During your experiment, you use the combinations listed below and record your observations. 

• You want to answer the question, “Will any liquid, when mixed with A+B turn green?” In order to obtain the data to answer this question, you need to do which additional experiments?

•  Add liquid 3 to A+B, liquid 4 to A+B, liquid 5 to A+B, and liquid 6 to A+B (52%, 43%)*

• Add liquid 3 to C+D, liquid 4 to D+E, liquid 5 to E+F, and liquid 6 to A+F (13%, 16%)

• Add liquid 4 to B+C, liquid 5 to C+D, liquid 6 to D+E, and liquid 1 to E+F (13%, 21%)

• Add liquid 1 to A+C, liquid 1 to A+D, liquid 1 to A+E, and liquid 1 to A+F (21%, 20%)

Data From My Chemistry ExperimentsLiquid Powders Observations

1 A + B Got hot, turned green2 A + B Got hot, turned green, bag exploded1 A + C Got hot, turned pink2 B + C Got cold, turned purple

• You have the following chemicals: 6 liquids labeled 1-6 and 6 powders labeled A-F. You combine two powders and one liquid in a Ziploc bag, mix and record your observations. During your experiment, you use the combinations listed below and record your observations. 

• What is the best conclusion that you can draw based upon this data?• All chemicals when mixed together turn cold. (32%, 27%) • Liquid 1 makes bags explode. (8%, 16%) • Whenever you add powders D and B to any liquid, it gets cold. (52%, 45%)* • Whenever you add powders D and B to any liquid, it fizzes. (8%, 12%)

Data From My Chemistry ExperimentsLiquid Powders Observations

1 D + B Gets cold, turns blue, bag explodes2 D + B Gets cold, turns blue, fizzes3 D + B Gets cold, turns blue4 D + B Gets cold, fizzes5 D + B Gets cold, turns purple, texture changes6 D + B Gets cold, thickens, turns green