4. How does structure influence reactivity?

“How does structure influence reactivity?” is a question of connection between chemical structure and behavior. The specific ways in which the submicroscopic particles of matter interact with each other and are transformed into different chemical species depend on their atomic composition and molecular structure. The types of atoms present in a molecule and their relative arrangement  in space affect the distribution of the electrons that can participate in bonding processes with other particles. Understanding how molecular structure affects electron distribution, and how this in turn determines how different particles interact and react with each other is critical to design the synthesis of desired materials and to control chemical processes.

This formative assessment was developed by a past ACCT cohort member.

 

The Dietary Calories formative assessment asks students to do an energy survey to probe how students think about energy in their diets. The formative assessment task reveals students’ thinking about structure-property relationships and chemical mechanism by getting students to look at food labels to try to figure out where in the ingredients the calories come from. Students are asked to share and explain their thinking about the energy content in food and justify their explanations based on models of structural formulas of some ingredients. Students reveal even more thinking about structure-property relationships when asked to explain the relationships between the energy content in food and the energy changes witnessed in combustion reactions.