Predicting solubility using HSAB and Bronsted acid/base strength

Submitted by Michelle Personick / Wesleyan University on Wed, 06/23/2021 - 16:37
Description

This activity is a guided approach to answering the following: "Give an example of a silver (Ag+) salt that is expected to be soluble in water." It requires students to consider both HSAB and Bronsted acid/base concepts when evaluating solubility.

I use the activity at the end of the unit on reactivity of ions in aqueous solutions, after we have gone over all of the relevant concepts, and the question (without scaffolding) is similar to what I might ask on an exam.

Predicting reactivity with the HSAB principle

Submitted by Michelle Personick / Wesleyan University on Wed, 06/23/2021 - 16:07
Description

This activity is designed to give students practice with predicting the preferred direction of double displacement reactions using the hard-soft acid-base (HSAB) principle. It includes a question where students must determine the relative softness of two soft bases. This activity was used after the lecture where students were introduced to these concepts.

Acids, Bases, and Solubility Rules

Submitted by Michelle Personick / Wesleyan University on Wed, 06/23/2021 - 15:07
Description

This activity is designed to serve two purposes. The first is to give students practice with assigning the acidity of cations (acidic or non-acidic) and the basicity of anions (basic, feebly basic, or non-basic). The second is to guide students to discover the general trends in solubility for combinations of Bronsted acids and bases. The thermodynamic underpinnings of these generalized "solubility rules" are taught in the subsequent lecture.

Determining the Basicity of Oxo Anions

Submitted by Michelle Personick / Wesleyan University on Wed, 06/23/2021 - 12:50
Description

This is an in-class activity that I use in my advanced general chemistry course to teach students how to qualitatively assign oxo anions as non-basic, feebly basic, or basic. Being able to qualitatively make these assignments helps students when we get to predicting solubility of compounds using Bronsted acidity and basicity.

Reactions of cations with water

Submitted by Michelle Personick / Wesleyan University on Wed, 06/23/2021 - 12:38
Description

This is an in-class activity that I use in my advanced general chemistry course to teach students how to rank the relative acidity of monoatomic cations and how to qualitatively predict the strength of the interaction of these cations with water (hydration and hydrolysis).

Introduction to reactions of ions with water

Submitted by Michelle Personick / Wesleyan University on Wed, 06/23/2021 - 12:08
Description

This is an in-class activity that I use in my advanced general chemistry course right before I start teaching about the relationship between the Bronsted acidity of cations and their hydration/hydrolysis. This is the first topic in the course (reactions of ions in aqueous solution), and we would have just spent a lecture reviewing intermolecular forces. 

Basics of Redox Reactions

Submitted by Austin Scharf / Oxford College of Emory University on Wed, 05/26/2021 - 13:56
Description

This worksheet was designed as an in-class, group activity in a flipped classroom. It relies on an understanding of the octet rule and common charges of various elements, as well as basic nomenclature of ionic compounds.  The worksheet teaches students to balance simple redox reactions (in which only the oxidized and reduced atoms are present) by identifying half-reactions, counting electrons transferred, and multiplying half-reactions to "cancel" electrons.  

nanoCHAt #5: Effective Feedback part 1

Submitted by Hilary Eppley / DePauw University on Tue, 05/04/2021 - 10:34
Description

A nanoCHAt conversation about ways that instructors can give effective feedback to students without creating unrealistic workloads for the instructor. Recorded by VIPEr Fellows Tendai Gadzikwa, Kari Young, and Dean Johnston with Hilary Eppley (moderator) on April 9, 2021.  The full nanoCHAt playlist can be acccessed at https://www.youtube.com/playlist?list=PL2wnHWA8OaA5Y6pPaOk2zt6wwrd2HK6kP

nanoCHAt #4: Leveling the Playing Field, part 1

Submitted by Shirley Lin / United States Naval Academy on Wed, 04/28/2021 - 13:26
Description

A nanoCHAt conversation about ways that instructors can level the playing field for students coming into a course with a variety of academic backgrounds. Recorded by VIPEr Fellows Kate McCusker, Abdul Mohammed, Janet Schrenk, and Andrea Van Duzor with Shirley Lin (moderator) on April 2, 2021.  The full nanoCHAt playlist can be accessed at https://www.youtube.com/playlist?list=PL2wnHWA8OaA5Y6pPaOk2zt6wwrd2HK6kP