Organic mechanisms meet oracy

‘What did you say?’, exclaimed the student next to me in a seminar at the start of my chemistry degree. ‘It’s a secondary carbocation,’ I replied. What I had said wasn’t wrong, just how I said it. Instead of pronouncing the hard t in carbocation, I had used a soft t to rhyme with station. How had I made it through A-level chemistry without knowing how to say this vital term?

My inability to pronounce this word raised two questions for me. Firstly, was I being held back by not being able to verbally communicate ideas, and secondly, if I had not experienced using this terminology, what else had I missed or misunderstood during my A-level? While this memory makes me shudder, it highlights the importance of talk and oracy in teaching mechanisms in organic chemistry.

Talk allows students to explore ideas and exposes misconceptions 

Oracy involves explicitly teaching students to talk and through talk. While mechanisms may seem to be more about drawing than speaking, there is a vast pool of vocabulary that students need to communicate. Furthermore, students understand mechanisms better through talk. Talk allows them to explore ideas and exposes misconceptions, such as the carbocation situation. I’ve found that encouraging my students to talk about their mechanisms is a powerful tool for understanding the underlying chemistry. I recommend you try it.

The power of oracy

We start by providing a glossary (either online or on paper) of a few key terms such as electron rich, delta charge and my old nemesis, carbocation. As we introduce new words, teachers demonstrate correct pronunciation and students practise through choral repetition. Teachers then give students diagrams of a mechanism to describe out loud in pairs, using words from their glossary. We do this before they encounter mechanisms from the specification, and all through talk, not writing, so that they can grapple with ideas and change their minds as they speak.

After trialling this approach, I found that students needed more than just a word list. They needed model phrases, which may not be on the specification but allow for a much richer description of what is happening in any mechanism, for example nucleophilic attack or flow of electrons.

Once students have practised speaking the language of mechanisms, they work in small groups to solve problems, talking through where electrons may move. I often use a ‘what happens next?’ style of question. Oracy prompts and sentence stems such as ‘the ammonia in this mechanism is a nucleophile because …’ and ‘the lone pair of electrons flow towards …’ are valuable scaffolds that you can fade over time.

Speaking these out loud allows more fluid problem solving. Students can correct or adapt their answers as they speak and challenge each other’s ideas more easily than when they commit them to paper. After this practice, students are more able to confidently approach specification mechanisms.

Using an oracy-based approach is not always easy for students. Some can be nervous about speaking in front of peers, others are afraid of making mistakes. Providing prompts and choral repetition reduce some of this fear. Most of all, creating a culture of positive mistakes is really helpful. I start my topic by sharing my own mistake with carbocations. This puts them at ease and allows for humour at my expense!

Oracy has real power for teaching organic mechanisms. Students learn to talk, becoming confident communicators who use the language of mechanisms effectively. They also learn through talk, by speaking to each other to solve problems rather than by rote-learning diagrams.