Solubility of Glucose Model

thingiverse

This model showcases the process by which covalent compounds like glucose dissolve in water. The carbon atoms (black), oxygen atoms (pink), and water molecules are all to scale. Separate molecules can be printed out and placed on top of the molecule, repeating its structure. Using the included water molecules, the dissolving of a covalent compound can be demonstrated by removing the individual molecules. Files are available for printing the model on dual extruder printers (recommended) and single extruder printers. The glucose crystal file for a single extruder is too large to export as an STL, so a single layer is included which can be printed multiple times and glued together. Print Settings Printer: Flash Forge Creator Pro Rafts: Yes Supports: Yes Resolution: .2mm Infill: 15% Standards NGSS CCSS Overview and Background Students often struggle to understand the concept of solubility on a particle level. This model can be used to demonstrate how a molecular compound separates into molecules when dissolved, also showing the structure of covalent crystals. Students should be familiar with the differences between ionic and molecular compounds before using this model. Objectives: - Students will describe the process by which a molecular compound dissolves in water. - Students will explain how water molecules interact with covalent compounds through intermolecular forces. - Students will explain why certain substances can form crystal structures. Lesson Plan and Activity Show students some glucose or sucrose and ask what will occur when the molecules are dropped into water. Discuss what occurs on the macro level (it dissolves) and then ask students to draw what they think will happen on the particle level. Show the model of glucose already set up with one or more layers of the individual molecule pieces on top. Pour some water on the model by dropping the water molecules included in the set onto the model, knocking the individual molecules off the crystal. This can lead to discussions about how the water molecules interact with glucose molecules through hydrogen bonds, why the glucose molecules do not break apart, and about how the surface of the crystal must dissolve before the interior. Materials Needed No other materials are needed besides the model kit, although a document camera may be helpful in demonstrating how the model works.