This blog is designed to supplement my presentation at the National Science Teaching Association Conference in Minneapolis in November 2025.
Abstract
The concepts covered in a general chemistry II course are designed to teach students concepts applicable to future chemical studies. However, these seemingly disconnected concepts can be frustrating and confusing for students without understanding their relevance in a real-world situation. This presentation will discuss the use of ocean acidification (OA) as an overarching research project designed to tie concepts discussed in general chemistry II courses to a current environmental issue. Using case studies, guided inquiry experimentation, scientific literature, and real-world data, students will learn how chemical equilibrium, acid/base chemistry, solubility, and other concepts addressed in general chemistry apply to the study of OA. This presentation will provide educators with resources on OA and an example of utilizing them in the general chemistry classroom.
Attendees will learn how to incorporate ocean acidification, a climate change topic, into a post-secondary general chemistry course by linking it to content already discussed in the course.
Presentation Slide Deck
Introduction
I developed the idea to incorporate a study of ocean acidification into my General Chemistry II class while on sabbatical during the 2018-19 academic year. My goal was to provide a real-world application for the concepts covered in a general chemistry II course and unite the seemingly disjointed topics covered in the course. I later included a Course-Based Undergraduate Research Experience (CURE) component in the form of a guided-inquiry lab. I previously posted about this work. This blog is an update of that work.
This class uses the OpenStax General Chemistry 2e textbook and D2L Brightspace as the Learning Management System (LMS).
Literature Review and Resources
Students complete a lesson on reliable sources and scientific resources in General Chemistry I. Students also complete an analysis of drinking water quality in General Chemistry I, so they are already familiar with water chemistry. They continue to build on this knowledge in General Chemistry II. A full list of literature review and resources is provided in my previous blog post on this topic. Additional resources I have identified since July 22 are provided below:
Brunning, A. (2016, June 30). Ocean Acidification and Chemical Signaling. Compound Interest. https://www.compoundchem.com/2016/06/30/ocean-acidification/
Brunning, A. (2017, Jan 8). Ocean Acidification: The Other Carbon Dioxide Problem. Compound Interest. https://www.compoundchem.com/2017/01/18/ocean-acidification-co2/
CBS Sunday Morning. (2025, Mar 23). Is Carbon Capture a Solution to the Climate Crisis?. [Video]. YouTube. https://youtu.be/YKDYjXgdJmU?si=eQ6IuzgxyVbQd29D
Geo Girl. (2020, Oct 1). Ocean Acidification-Reaction Explanation and Carbonate Level Projections. [Video]. YouTube. https://youtu.be/q-wKckDkEg0?si=4gtRPxnqoV2PGOzq
Geo Girl. (2024, Feb 18). How Ocean Chemistry Affects Global Climate and Vice Versa. [Video]. YouTube. https://youtu.be/f9cIOhEiO8M?si=-I8ltbuvCvkpVCrU
Geo Girl. (2024, Mar 3). Causes and Effects of Ocean Warming, Acidification, Anoxia, and Sea Level Rise. [Video]. YouTube. https://youtu.be/M2Gn97NZHTE?si=5XPgkFrScLyL7wV4
Just Have a Think. (2022, May 1). Carbon Dioxide Removal From Our Oceans. [Video]. YouTube. https://youtu.be/kzMWIrh6bL4?si=9iBrExEhbUE0z1G5
La Plante, E.C., Simonetti, D.A., Wang, J., Al-Turki, A., Chen, X., Jassby, D., &, Sant, G.N. (2021). Saline Water-Based Mineralization Pathway for Gigatonne-Scale CO2Management. ACS Sustainable Chemistry & Engineering. 9 (3), 1073-1089. https://pubs.acs.org/doi/full/10.1021/acssuschemeng.0c08561
Leavitt, K. (2016, Sept 4). Ocean Acidification or Osteoporosis of the Sea? Seacot Science Center. https://www.seacoastsciencecenter.org/2016/09/14/ocean-acidification-osteoporosis-sea/
Middelburg, Jack. (2019). Biogeochemical Processes and Inorganic Carbon Dynamics. https://www.researchgate.net/publication/330643417_Biogeochemical_Processes_and_Inorganic_Carbon_Dynamics
N.D. (1990). The CO2-Carbonic Acid System and Solution Chemistry. In Morse, J.W. & Mackenzie, F.T. (Ed.), Developments in Sedimentology (pp1-38). Elsevier. https://doi.org/10.1016/S0070-4571(08)70330-3
Assignments
The assignments used in this course of study have changed over the past 6 years. Initially, students completed a few smaller assignments and case studies on OA and then submitted a large project at the end of the semester. I have adjusted this over the years. Students no longer complete a large end-of-semester project. Instead, they address similar learning outcomes in a series of smaller assignments. They complete approximately one assignment each unit of the class. Below is a summary of each assignment:
Pre and Post Surveys
Students are asked to complete a pre-survey on the first day of class and a post-survey on the last day of class to assess their learning during the course. Students are asked to identify acids, bases, and salts; explain the causes of OA and how it impacts ocean waters and other organisms; write the chemical equations for how oceans absorb carbon dioxide, and identify sources of carbon dioxide. Each survey is worth 10 points. Students receive credit for completing each survey, regardless of their answers. I will report on this data later in this post.
An Investigation into Ocean Acidification Case Study
I use this case study to introduce the concept of OA during the first week of lab and outline the project. I have heavily edited this case study over the years to include other resources and new information. I also review the resources available to students for use during the semester (open-educational resources (OER), Riverland library resources, etc.) and introduce the first assignment they will need to submit on OA.
OA Assignment 1 – Evidence Refuting OA
When researching a topic, it’s important to look at all of the research available, including resources that refute your findings. Part of doing the research is assessing each source and determining its merit and reliability. Students are required to find two sources that refute OA and evaluate them to determine if they’re reliable. Students are allowed to submit a written or video assignment presenting their source and evaluation. Students need to fact-check the content of the source and determine if the data is supported by empirical evidence. They also need to access the source to determine the author’s motives, content knowledge, and bias. I also tell students that if they have trouble finding two sources, they should also discuss this. The lack of evidence refuting a phenomenon either says this hasn’t been studied or that the evidence overwhelmingly supports that OA is occurring. This assignmetn is worth 25 points.
OA Assignment 2 – Chemistry of OA
Once we break down the chemical process of ocean acidification and it’s impact on ocean pH, students need to explain this process in their own words. Students are asked to include the following in their submission:
- Discuss the general chemistry of the oceans. Outline common dissolved ions found in ocean water.
- Outline how the increase in atmospheric carbon dioxide has impacted ocean chemistry.
- Provide a brief overview of the chemistry involved in ocean acidification, including the chemical equations for how OA occurs.
- Explain how this ocean chemistry impacts the ions available for shellfish to build and maintain their shells.
- Your discussion should also apply Le Chatelier’s Principle and solubility to ocean chemistry. How do these principles apply to ocean acidification and its impact?
This assignment is worth 25 points and students can submit a written or video assignment.
OA Assignment 3 – OA Solutions
Students research and present one possible solution to address OA. They submit their assignment to a discussion board do the entire class can review these solutions. Students submit a written or video assignment summarizing the solution (this can be a published idea or a solution of their own creation) and analyzing its viability. Students need to analyze their sources for reliability in their reference list. This assignment is worth 25 points.
OA Assignment 4 – OA Final Reflections
Students are asked to reflect on their learning during the semester in a final written or video-recorded assignment that addresses the following questions. This assignment is worth 25 points.
- What surprised you regarding OA? Why?
- Is this phenomenon concerning to you? Why or why not? Use the information you learned during this semester to support your opinion. I want you to provide a clear and informed opinion, whatever your opinion.
- Did this project help improve your understanding of chemistry as it applies to the world? Why or why not?
- From what you read on the Ocean Acidification Solutions Discussion Board, is there a solution that seems most promising to you? Explain your reasoning.
- Do you feel more equipped to conduct literature research, assess the source for reliability, and develop an informed opinion? Explain your answer with supporting evidence.
- What was your favorite part of this project? Why?
- What is one thing you would change about this project? Why? Please be honest and constructive. Your feedback will help me improve this project in the future.
OA Guided-Inquiry Experiment
Since 2022, students have completed a guided inquiry lab on ocean acidification. Initially, I had students create their own buffers using the Henderson-Hasselbach equation; however, this did not work as well as I’d hoped due to time constraints and the limitations of our stockroom and budget. Last year, we purchased pre-made buffer solutions in pH 6, 7, 8, and 9 for students to use, which worked much better.
Previously, I also completed a case study the week before this lab on Equilibria in the Environment; however, some of the information discussed in this case study was already introduced in the An Investigation into Ocean Acidification Case Study completed during the first week of the semester. Because of this, I heavily edited down the Equilibria case study and included the content either in the first case study or absorbed it into the OA experiment as a way to introduce the experiment. I now present an interactive lecture on Ocean Chemistry and Equilibrium before students begin work on their guided inquiry lab.
I provide students with a list of materials and experimental guidelines and expectations. Students then work with their lab partner to write an experimental procedure, create data tables, and begin their experiment. They collect data on their experiment over 4 weeks and then analyze the data to determine if it supports the concept of ocean acidification. They report on their data, offer ideas on how to improve the experiment, and post their lab reports in the discussion boards on Brightspace. This sharing of information in a “public” forum simulates how scientists publish their research.
This experiment is still a work in progress. Students don’t see a significant change in the mass of the shells over time, which students find disappointing. Part of this is due to the limited amount of time for students to run their experiments (approximately 4 weeks). I also plan to have students make one buffer solution in the future so they have an opportunity to apply the Henderson-Hasselbach equation in the laboratory.
