I’ll Change Your Mind (about chemistry)

When I got to college, I took general chemistry in my first semester. The lecture hall was filled with 175 students, mostly freshman, who were on tracks to go into engineering, medical, or STEM fields. The environment felt competitive and fast-paced, as we jotted down notes quickly to keep up with the lecture. I was planning on being a high school chemistry teacher and after taking AP Chemistry in high school, I felt confident and eager to learn. However, it didn’t take long until I reached concepts that were confusing and problems I struggled to solve. The more I learned, the more I realized what I had remembered from high school chemistry was slightly wrong or inaccurate. So, what happens when you start learning concepts or ideas that contradict your prior knowledge? What do you do?

Have you ever been in a position where your initial conceptions were challenged or even contradicted in school? Think back to how your knowledge about science has changed over time. As a future teacher, addressing misconceptions is a key part to teaching any subject, as students enter your classroom not as clean slates, but as people with unique amounts of prior knowledge and experiences.

Key Ideas about Misconceptions:

1. Knowledge is constructed in the mind of the learner. Students often struggle to take their knowledge about a context beyond the classroom or subject in which they learned it. Chemistry knowledge tends to be domain-specific, which can make it difficult for application.
2. Misconceptions are resistant to instruction. Research has shown that misconceptions are hard to change in the mind of a learner, as it requires lots of time and repeated effort.
3. Knowledge is not the same as understanding. As we know, students can possess knowledge or memorize information, but lack understanding or the ability to explain a concept adequately.
4. Misconceptions are often instructor-driven. Misconceptions are going to come from past experiences, misuse of or confusion with science language, or by simplified explanations from instructors.

source: “I Have Found You an Argument: The Conceptual Knowledge of Beginning Chemistry Graduate Students” by George M. Bodner

Did you know? Common Chemistry Misconceptions

1. Ionic bonding requires the transfer of electrons. WRONG!

Ionic bonding, such as in sodium chloride, is a process that doesn’t actually require electron transfers. This idea is driven by the Bohr Model, where sodium’s one valence electron “moves” to chloride’s one vacant space on its outer shell and by the saying kids learn in chemistry class, that “ionic bonding is the transfer of electrons and covalent bonding is the sharing of electrons.” In reality, bonds have varying degrees of different bonding character, which is more of an abstract concept, but can be explained by the figure below.

2. Electrons move around an atom’s nucleus in circular orbitals. WRONG!

Students learn in school all the time about the Bohr Model and how electrons move in a circular path in distinct orbits around the nucleus of an atom. However, atom’s nuclei are surrounded by an electron cloud, where the electrons do not exist only in one location around an atom. Again, a model is perpetuating a false idea about a core chemistry concept. Check out this video to learn more!

3. Gibbs free energy (deltaG) is always less than 0 for a spontaneous process. WRONG!

Many students have misconceptions in thermodynamics, specifically surrounding heat. At least for me, I had always learned that deltaG < 0 for a process to be considered spontaneous. However, this is true for only isothermal, constant pressure changes. However, for non-isothermal cases, the sign of delta G cannot predict spontaneity. Read about misconceptions in thermodynamics in an JCE article here.

Moving Towards Conceptual Change

Once students’ misconceptions have been identified, teachers and learners can work to redevelop them, in a process called conceptual change. The video below is super helpful for learning about conceptual change and how it’s done!

Simply countering a student’s misconception with the correct idea isn’t enough. We’ve developed mental models over time that have supported our misconceptions, so a mental model won’t just “go away” and be replaced with the new idea.

What Teachers CAN Do

1. Seek to understand WHY students’ hold certain misconceptions. If you don’t know them and their prior knowledge, you won’t be able to address them in your class. Start new units with activities to assess students’ prior knowledge and what they know before you start to teach to be more informed!
2. Make the idea INTELLIGIBLE! Explain the new idea with language the students are already familiar with. By connecting concepts to students interests’ or the real world, the new explanation may seem more reasonable to the student. Have students describe the new idea in their own words too.
3. Make the idea FRUITFUL! Help students see how their preconceived idea was incorrect and why the new one is through demonstrations, hands-on experiments, and inquiry activities. When they can physically see why a concept works, they’ll start to let go of their old misconception. Start applying this new concept to solve problems in order to reinforce the new idea.

An important, gentle reminder — Teachers will have misconceptions of their own, too! Yet, we are all lifelong learners and science is always changing. For me, when I initially found out that ionic bonding wasn’t the transfer of electrons, it felt like everything I knew about bonding wasn’t correct anymore. It’s a scary feeling, so keep that in mind as your students work through misconceptions of their own!

We can inform our students that the nature of science is everchanging and complex and that with more research and discovery, models often get replaced with ones that are more accurate. Conceptual change is vital to the learning process, so embrace it and encourage it in your students! It’ll serve them in the long run – in their future classes, careers, and endeavors.

Find those misconceptions in your students, address them in an intelligible way, and keep building on it! It takes time, but it’s worth it.

Keep going! Until next time, Miss Creeden