Chemical Reaction Rates: Inquiry on Affecting Factors

Contributor
CPALMS Lesson Plan Development Initiative
Type Category
Instructional Materials
Types
Instructor Guide/Manual , Interactive Simulation , Experiment/Lab Activity
Note
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be “fully aligned,” the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.

Reviews

Description

This lesson focuses on having students examine the effect of different factors on the rate of a chemical reaction, including: temperature, concentration of particles, surface area of reactants, and the presence of catalysts. Activities organized at lab stations allow students to explore each factor with minimal teacher guidance.  These activities are combined with online simulations in the lesson to support students in developing a molecular level understanding of how and why each factor affects the rate of  change.

Intended Audience

Educator and learner
Educational Level
  • Grade 12
  • Grade 11
  • Grade 10
  • Grade 9
  • High School
Language
English
Access Restrictions

Free access - The right to view and/or download material without financial, registration, or excessive advertising barriers.

Performance Expectations

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.

Clarification Statement: Emphasis is on student reasoning that focuses on the number and energy of collisions between molecules.

Assessment Boundary: Assessment is limited to simple reactions in which there are only two reactants; evidence from temperature, concentration, and rate data; and qualitative relationships between rate and temperature.

This resource is explicitly designed to build towards this performance expectation.

Comments about Including the Performance Expectation
The combination of hands-on exploration at lab stations combined with online simulations of molecular level representations in this lesson allows students to explore the effects of different factors on the rate of a reaction. It is important that the classroom implementation of these resources focuses on making explicit connections between students’ observations from the lab stations and the online simulations in order to fully meet the performance expectation. See specific tips below for additional details.

Science and Engineering Practices

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
The lesson plan includes questions for each station that provide an opportunity for students to construct an argument about how the factor they are investigating affects the rate of a reaction. After completing the activity at the station, students are asked to identify which reaction at that station had the fastest rate and to explain what might be occurring at the molecular level that could account for that result. Teachers should have students refer back to the simulations as evidence to support their ideas for why the change occurs, referencing the number and energy of collisions between molecules. Teacher could extend the connection to the argumentation practice by having student present their responses to the lab questions for critique by their peers.

This resource was not designed to build towards this science and engineering practice, but can be used to build towards it using the suggestions provided below.

Comments about Including the Science and Engineering Practice
To fully engage student thinking about the effects of each of the factors they are examining in this lesson, students should make predictions of what change to the reaction rate will result from the activity at each lab station. The order of activities outlined in the lesson plan starts with engaging students with a demonstration and online simulations related to the factors to be tested at each of the lab stations in the second part of the lesson. This introduction provides substantial background knowledge for students to refer to when making predictions at a lab station.

Disciplinary Core Ideas

This resource is explicitly designed to build towards this disciplinary core idea.

Comments about Including the Disciplinary Core Idea
As noted above, the questions at each lab station ask students to explain the results based on molecular-level events. It is important for a teacher to provide time for students to discuss these ideas both in small groups as well as a whole class before having students respond to the essential questions after the lab activities as these questions ask students to apply their learning. The discussion should focus on connecting the observed results at each station and how that can be explained by the collisions of molecules.

Crosscutting Concepts

This resource appears to be designed to build towards this crosscutting concept, though the resource developer has not explicitly stated so.

Comments about Including the Crosscutting Concept
The focus of this lesson is on examining the change in the rate of a chemical reaction when a factor is changed. Students analyze the effects of changing each factor at both the macroscopic and molecular levels with the use of the online simulation as well as lab work. Teachers should help to draw students attention to considering what changes as well as noticing what stays the same as they make their observations.

Resource Quality

  • Alignment to the Dimensions of the NGSS: The lesson, the activities and associated resources, provide explicit opportunities for students to work with each of the three dimensions from NGSS if used according to the tips provided here. The three dimensions work together throughout the lesson to support students to make sense of phenomena. It is important for teachers to keep in mind each of these dimensions as they implement the activities in the classroom.

  • Instructional Supports: All components of the lesson work together to provide opportunities for students to engage in understanding phenomena and apply that understanding. The lesson introduction engages students with a demonstration and online simulations to access their prior knowledge so that the lesson activities builds on what they already know about molecular motion and chemical reaction rates. The questions for each lab station provide opportunities for students to express and justify their ideas, including consideration of how to represent the molecular level model of the phenomena. Suggestions for accommodations and extensions for the lesson are provided for the teacher to differentiate their instruction. Further supports may be needed for students that may struggle to express their ideas, including English language learners. Another improvement on the lesson would be to add to the closure of the lesson by asking students to identify connections to their own experiences.

  • Monitoring Student Progress: Guidance is provided for teachers to assess student prior knowledge at the start of the lesson and student proficiency at the conclusion of the lesson using methods, vocabulary, representations, and examples that are accessible and unbiased for all students. However, it is left to the teacher to consider how to monitor student progress throughout the station work. This may include holding short conferences with each group. The conferences provide an opportunity for the students to prepare to communicate their results in a whole class discussion, and provides the teacher with data to use in planning appropriate ways to support students in practices of engaging in argumentation with evidence in ways that connect to the disciplinary core ideas and crosscutting concepts.

  • Quality of Technological Interactivity: The online simulations included in this lesson are generally intuitive but there are no directions provided on using them to support student learning in this lesson (though basic directions are provided from the simulations webpage). Each of the recommended simulations has limited options, but the options are sufficient for analyzing the effects of each factor on the molecular motions and collisions. These resources are great for use with interactive whiteboard for whole class discussion or for students to explore on tablets or other devices. As the simulations require Shockwave, use may be limited for some devices.