About Reaction Rates

The Standards
Reaction Rates is an NGSS-inspired task that consists of four parts. As a whole, the activity is designed to focus students attention upon the effect of reactant concentration and temperature upon the rate of a reaction. They use data to predict and to identify the effect of these two variables upon reaction rate. And they use the Collision Model to explain why such an cause-effect relationship exists. The activity addresses the HS-PS1-5 Performance Expectation of the Next Generation Science Standards. 

This NGSS-inspired task consists of four parts. Each part involves a different type of skill or understanding. Collectively, the four parts were designed to address the following NGSS performance expectation:


HS-PS1-5:
Apply scientific principles and evidence to provide an explanation about the effects of changing the temperature or concentration of the reacting particles on the rate at which a reaction occurs. 


As a whole, the questions in this task address a wide collection of disciplinary core idea (DCI), crosscutting concepts (CCC), and science and engineering practices (SEP). There are 46 multi-part questions organized into 14 Question Groups and spread across the four activities. Each question is either a 2D or (preferably) a 3D question. That is, the task of answering the question requires that the student utilize at least two of the three dimensions of the NGSS science standards - a DCI, a CCC, and/or an SEP.


The following DCI, SEPs, and CCCs are addressed at some point within Reaction Rates:

DCI:  PS1.B: Chemical Reactions

• Chemical processes, their rates, and whether or not energy is stored or released can be understood in terms of the collisions of molecules and the rearrangements of atoms into new molecules, with consequent changes in the sum of all bond energies in the set of molecules that are matched by changes in kinetic energy.

SEP 2.3:  Developing and Using Models
Develop, revise, and/or use a model based on evidence to illustrate and/or predict the relationships between systems or between components of a system.


SEP 6.3:  Constructing Explanations and Designing Solutions
Apply scientific ideas, principles, and/or evidence to provide an explanation of phenomena and solve design problems, taking into account possible unanticipated effects.


CCC 1.1: Patterns
Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.


CCC 2.3: Cause and Effect
Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.


CCC 7.1: Stability and Change
Much of science deals with constructing explanations of how things change and how they remain stable.

 

 

Here is our NGSS-based analysis of each individual activity of The Ammonia Factory Science Reasoning task. The core ideas, crosscutting concepts, and science and engineering practices that we reference in our analysis are numbered for convenience. You can cross-reference the specific notations that we have used with the listings found on the following pages:  

Disclaimer: The standards are not our original work. We are simply including them here for convenience (and because we have referenced the by number). The standards are the property of the Next Generation Science Standards.

 

Part 1: Paragraph Completion

This activity involves two paragraph-completion exercises. Students use a word/phrase bank to select missing words and phrases in order to complete a paragraph. There are two such paragraphs; both paragraphs contain 8 blanks. Once students complete their paragraph, they can submit their answers for evaluation and feedback. On each answer submission, they are told the number of correct blanks but not told which blanks are correct. Students have an unlimited number of opportunities to correct their answers. Students earn the Trophy for the activity once they correctly complete both paragraphs.


NGSS Claim Statement: Use the Collision Model of reaction rates to provide an explanation as to how and why concentration and temperature have the effect that they do upon the rate of reaction.

 

Target DCI(s)	Target SEP(s)	Target CCC(s)
Chemical Reactions PS1.B Chemical processes, their rates, and whether or not energy is stored or released can be understood in terms of the collisions of molecules and the rearrangements of atoms into new molecules, with consequent changes in the sum of all bond energies in the set of molecules that are matched by changes in kinetic energy.	Constructing Explanations and Designing Solutions SEP 6.3 Apply scientific ideas, principles, and/or evidence to provide an explanation of phenomena. Developing and Using Models SEP 2.3 Use a model based on evidence to predict the relationships between systems or between components of a system.	Patterns CCC 1.1 Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena. Cause and Effect CCC 2.3 Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.

 

Part 2: Ranking Tasks

This activity consists of 12 forced-choice questions organized into four Question Groups. A reaction is described and information regarding the concentrations of reactants and the temperature are provided for three trials. Students must rank the reaction rates for each of the three trials - from lowest to middlest to greatest. Students earn the Trophy for the activity when they demonstrate mastery of all four Question Groups.

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NGSS Claim Statement: Use the Collision Model of reaction rates to predict the greatest and lowest reaction rate from among three given conditions.

 

Target DCI(s)	Target SEP(s)	Target CCC(s)
Chemical Reactions PS1.B Chemical processes, their rates, and whether or not energy is stored or released can be understood in terms of the collisions of molecules and the rearrangements of atoms into new molecules, with consequent changes in the sum of all bond energies in the set of molecules that are matched by changes in kinetic energy.	Constructing Explanations and Designing Solutions SEP 6.3 Apply scientific ideas, principles, and/or evidence to provide an explanation of phenomena. Developing and Using Models SEP 2.3 Use a model based on evidence to predict the relationships between systems or between components of a system.	Cause and Effect CCC 2.3 Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system. Stability and Change CCC 7.1 Much of science deals with constructing explanations of how things change and how they remain stable.

 

Part 3: Cause and Effect

This activity consists of 16 forced-choice questions organized into four Question Groups. Students are given a table of data that illustrate a clear pattern of reaction rates. They must identify the relationship exhibited in the table and explain the relationship in terms of such variables as collision frequency, particle speed, particle kinetic energy, etc. Students earn the Trophy for this activity once they demonstrate mastery on all four Question Groups. 
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NGSS Claim Statement: Identify the pattern associated with reaction rates and temperature and reactant concentration and use the Collision Model of reaction rates to explain the causes that underly the patterns.

 

Target DCI(s)	Target SEP(s)	Target CCC(s)
Chemical Reactions PS1.B ​Chemical processes, their rates, and whether or not energy is stored or released can be understood in terms of the collisions of molecules and the rearrangements of atoms into new molecules, with consequent changes in the sum of all bond energies in the set of molecules that are matched by changes in kinetic energy. .	Constructing Explanations and Designing Solutions SEP 6.3 Apply scientific ideas, principles, and/or evidence to provide an explanation of phenomena and solve design problems, taking into account possible unanticipated effects.	Patterns CCC 1.1 Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.

 

Part 4: Case Studies

This activity consists of 16 forced-choice questions organized into four Question Groups. Students are provided data generated for a engineering design problem. They identify the next steps that should be taken in order to solve the problem according to the provided criteria. Students earn the Trophy for this activity once they demonstrate mastery on all four Question Groups. 
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NGSS Claim Statement: Use the Collision Model of reaction rates to predict the greatest reaction rate and relate the predictions to the behavior of the system at the particle level.

 

Target DCI(s)	Target SEP(s)	Target CCC(s)
Chemical Reactions PS1.B ​Chemical processes, their rates, and whether or not energy is stored or released can be understood in terms of the collisions of molecules and the rearrangements of atoms into new molecules, with consequent changes in the sum of all bond energies in the set of molecules that are matched by changes in kinetic energy.	Developing and Using Models SEP 6.3 Develop and/or use a model (including mathematical and computational) to generate data to support explanations, predict phenomena, analyze systems, and/or solve problems. Developing and Using Models SEP 2.3 Use a model based on evidence to predict the relationships between systems or between components of a system.	Patterns CCC 1.1 Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena. Cause and Effect CCC 2.3 Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.

 








Complementary and Similar Resources
The following resources at The Physics Classroom website complement the Reaction Rates Science Reasoning Activity. Teachers may find them useful for supporting students and/or as components of lesson plans and unit plans.

Concept Builders, Chemistry - Collision Model of Reaction Rates

The Physics Interactives, Chemistry - The Ammonia Factory Simulation