Description
Students develop a general model of solubility based on their own empirical data collected by reacting aqueous solutions of ionic compounds. The final investigation guides students through the effect of pH on calcium carbonate solubility. Students combine their knowledge from the hands-on activities with their analysis of the provided graphs (solubility vs. pH, solubility vs. temperature, and solubility vs. pressure) to make sense of the phenomenon of how cave speleothems form.
Time Requirement
Total, 265 minutes. Pre-lab, 100 minutes. Investigations 1 and 2, 90 minutes (combined). Investigation 3, 75 minutes. This activity is designed to take place over multiple periods.
Digital Resources
Includes 1-year access to digital resources that support 3-dimensional instruction for NGSS. Digital resources may include a teacher manual and student guide, pre-lab activities and setup videos, phenomenon videos, simulations, and post-lab analysis and assessments.
Crosscutting Concepts
Patterns
Science and Engineering Practices
Developing and Using Models
Learning Objectives
- Analyze student-generated empirical data for the purpose of developing and testing an evidence model of the solubility of ionic compounds in water.
- Determine the mechanism behind the dissolution of calcium carbonate leading to speleothem growth.
Prior Knowledge and Skills
Prior knowledge of ions, intermolecular forces, and types of chemical reactions is useful. Students should know how to write and balance chemical equations.