Observing a Chemical Reaction (NGSS Modified)

In a , I indicated that I would make available the Chemical Reactions lab that I modified to meet NGSS guidelines. Enjoy!

Concepts: 
models/modeling
solubility
Concepts: 

In this lab, students will address the concepts of chemical reactions, evidence for a chemical reaction, and devising hypotheses and experimental trials.

Procedure time: 
> 90 minutes
Prep time: 
10 minutes
Time required: 

2 53-minute class periods (about 2/3 of each class were used).

Materials: 
  • 1 baggie with zip seal
  • 1 plastic spoon
  • 1 10-mL of 25-mL graduated cylinder
  • 1 small container/canister
  • 1 plastic spoonful of sodium bicarbonate (baking soda)
  • 2 plastic spoonfuls of calcium chloride (road salt)

Optional materials

  • Digital balance
  • Infrared thermometer
Background: 

Research Question: How can you determine whether or not a chemical reaction takes place?

Background Knowledge:

  • When a chemical reaction occurs, the products that form have different properties than the initial materials.
  • Evidence of a chemical reaction.
  • Endothermic and exothermic reactions.
Procedure: 

Procedure:

  1. Recall the solubility data about sodium bicarbonate and calcium chloride. Indicate whether each is soluble or insoluble.
  2. Observe what the sodium bicarbonate looks like and record the data in your table.
  3. Place 1 tsp of the sodium bicarbonate in the plastic bag.
  4. Observe what the calcium chloride looks like and record the data in your table.
  5. Place 2 tsp of calcium chloride into the plastic bag.
  6. Observe if anything happens.
  7. Use a graduated cylinder to measure 10 mL of water and pour the water into the small container that was provided.
  8. Carefully set the water-filled container into the bag without spilling. Zip the bag closed while carefully removing air from the bag.
  9. Tip the container in the bag and record your observations.
Questions: 

Data Analysis:

  1. Did a chemical reaction take place? How do you know?
  2. Draw a model for what you perceive to be happening before and after mixing the substances with water.
  3. Assuming that a chemical reaction did take place, was the reaction dependent on the presence of sodium bicarbonate, calcium chloride, or both? Create a hypothesis and devise an experiment to test your hypothesis. Then do your experiment, record data and observations, and develop a conclusion based on your results. Draw another set of models that demonstrate what is happening according to your hypothesis and results.
Preparation: 

Gather all materials needed and walk students through lab expectations before going into the lab.

Attribution: 

Dan Meyers

Chemistry Teacher, Portage Central High School, Portage, MI 49002

ChemEdX Contributor

Collection: 

Safety

General Safety

For Laboratory Work: Please refer to the ACS .  

For Demonstrations: Please refer to the ACS Division of Chemical Education .

Other Safety resources

: Recognize hazards; Assess the risks of hazards; Minimize the risks of hazards; Prepare for emergencies

 

NGSS

Matter and its Interactions help students formulate an answer to the question, “How can one explain the structure, properties, and interactions of matter?” The PS1 Disciplinary Core Idea from the NRC Framework is broken down into three subideas: the structure and properties of matter, chemical reactions, and nuclear processes. Students are expected to develop understanding of the substructure of atoms and to provide more mechanistic explanations of the properties of substances. Chemical reactions, including rates of reactions and energy changes, can be understood by students at this level in terms of the collisions of molecules and the rearrangements of atoms. Students are able to use the periodic table as a tool to explain and predict the properties of elements. Using this expanded knowledge of chemical reactions, students are able to explain important biological and geophysical phenomena. Phenomena involving nuclei are also important to understand, as they explain the formation and abundance of the elements, radioactivity, the release of energy from the sun and other stars, and the generation of nuclear power. Students are also able to apply an understanding of the process of optimization in engineering design to chemical reaction systems. The crosscutting concepts of patterns, energy and matter, and stability and change are called out as organizing concepts for these disciplinary core ideas. In the PS1 performance expectations, students are expected to demonstrate proficiency in developing and using models, planning and conducting investigations, using mathematical thinking, and constructing explanations and designing solutions; and to use these practices to demonstrate understanding of the core ideas.

*More information about this category of NGSS can be found at 

Summary:

"Matter and its Interactions help students formulate an answer to the question, “How can one explain the structure, properties, and interactions of matter?” The PS1 Disciplinary Core Idea from the NRC Framework is broken down into three subideas: the structure and properties of matter, chemical reactions, and nuclear processes. Students are expected to develop understanding of the substructure of atoms and to provide more mechanistic explanations of the properties of substances. Chemical reactions, including rates of reactions and energy changes, can be understood by students at this level in terms of the collisions of molecules and the rearrangements of atoms. Students are able to use the periodic table as a tool to explain and predict the properties of elements. Using this expanded knowledge of chemical reactions, students are able to explain important biological and geophysical phenomena. Phenomena involving nuclei are also important to understand, as they explain the formation and abundance of the elements, radioactivity, the release of energy from the sun and other stars, and the generation of nuclear power. Students are also able to apply an understanding of the process of optimization in engineering design to chemical reaction systems. The crosscutting concepts of patterns, energy and matter, and stability and change are called out as organizing concepts for these disciplinary core ideas. In the PS1 performance expectations, students are expected to demonstrate proficiency in developing and using models, planning and conducting investigations, using mathematical thinking, and constructing explanations and designing solutions; and to use these practices to demonstrate understanding of the core ideas."

Assessment Boundary:
Clarification:

Students who demonstrate understanding can construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.

*More information about all DCI for HS-PS1 can be found at  and further resources at .

Summary:

Students who demonstrate understanding can construct and revise an explanation for the outcome of a simple chemical reaction based on the outermost electron states of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties.

Assessment Boundary:

Assessment is limited to chemical reactions involving main group elements and combustion reactions.

Clarification:

Examples of chemical reactions could include the reaction of sodium and chlorine, of carbon and oxygen, or of carbon and hydrogen.

Students who demonstrate understanding can use mathematical representations to support the claim that atoms, and therefore mass, are conserved during a chemical reaction.

*More information about all DCI for HS-PS1 can be found at  and further resources at .

Summary:

Students who demonstrate understanding can use mathematical representations to support the claim that atoms, and therefore mass, are conserved during a chemical reaction.

Assessment Boundary:

Assessment does not include complex chemical reactions.

Clarification:

Emphasis is on using mathematical ideas to communicate the proportional relationships between masses of atoms in the reactants and the products, and the translation of these relationships to the macroscopic scale using the mole as the conversion from the atomic to the macroscopic scale. Emphasis is on assessing students’ use of mathematical thinking and not on memorization and rote application of problem - solving techniques.

Join the conversation.

Comments 2

John Patrick's picture
John Patrick | Thu, 09/21/2017 - 21:48

Thank you, Dan.  This is straightforward, something I need for my classes heavy with IEP students.

Dan Meyers's picture
Dan Meyers | Thu, 09/28/2017 - 14:01

Thank you for the kind comment, John. Let me know how it goes for you.