1666 TEKS header image

Knowledge and Skills Statement

Science concepts. The student understands and can apply the factors that influence the behavior of solutions.

The further explanation is designed to be a resource for educators that helps them better understand the topic their students are learning. Further explanations may be written at a more complex level than would be expected for students at the grade level.

There are multiple sets of solubility rules that students can use, such as:

1. Alkali metal (Group IA) compounds are soluble.
2. Ammonium (NH4+) compounds are soluble.
3. Nitrates (NO3-), chlorates (ClO3-), and perchlorates (ClO4-) are soluble.
4. Most hydroxides (OH-) are insoluble. The exceptions are the alkali metal hydroxides and Ba(OH)2. Ca(OH)2 is slightly soluble.
5. Most chlorides (Cl-), bromides (Br-) or iodides (I-) are soluble. The exceptions are those containing Ag+, Hg+2, and Pb+2.
6. Carbonates (CO3-2), phosphates (PO4-3), and sulfides (S-2) are insoluble. The exceptions are the alkali metals and the ammonium ion.
7. Most sulfates (SO4-2) are soluble. CaSO4 and Ag2SO4 are slightly soluble.
BaSO4, HgSO4 and PbSO4 are insoluble.

It is less important that students memorize the solubility rules than that students are able to use them appropriately and consistently.

Glossary terms and definitions are consistent across kindergarten through high school in the TEKS Guide. The definitions are intended to give educators a common understanding of the terms regardless of what grade level they teach. Glossary definitions are not intended for use with students.

occurs when parts of two ionic compounds are exchanged, making two new compounds; also called a double displacement reaction

the degree to which a substance dissolves in a solvent (like water) to make a solution

Research

Baybekov, Shamkhal, Pierre Llompart, Gilles Marcou, Patrick Gizzi, Jean-Luc Galzi, Pascal Ramos, Olivier Saurel, Claire Bourban, Claire Minoletti, and Alexandre Varnek. "Will We Ever Be Able to Accurately Predict Solubility?" Scientific Data 11, no. 1 (2024):303. https://doi.org/10.1038/s41597-024-03105-6

Summary:  We investigated over 20 years of published solubility datasets and models, highlighting overlooked datasets and the overlaps between popular sets. We benchmarked recently published models on a novel curated solubility dataset and report poor performances. We also propose a workfow to cure aqueous solubility data aiming at producing useful models for bench chemists. Our results demonstrate that some state-of-the-art models lack a well-defined applicability domain and overlook historical data sources.

Research

Oliver, Rachel C., Thomas Nguyen, Hrithik Agarwal, Jeremy R. Phifer, Larissa Ferreira da Silva, Gabriel Gonçalves Nogueira, Ana Karolyne Pereira Barbosa, Ryan T. Ley, Elizabeth J. O’Loughlin, Brett T. Rygelski and et al. "Predicting the Solubility of Nonelectrolyte Solids Using a Combination of Molecular Simulation with the Solubility Parameter Method MOSCED: Application to the Wastewater Contaminants Monuron, Diuron, Atrazine and Atenolol." Processes 10, no.3 (2022):538. https://doi.org/10.3390/pr10030538

Summary:  Here, we demonstrate the ability to use a small number of molecular simulation free energy calculations to generate reference data to regress model parameters for the analytical MOSCED (modified separation of cohesive energy density) model. The result is an efficient analytical method to predict the equilibrium solubility of nonelectrolyte solids.