What is the pKa of water (and why do some textbooks get it wrong)?

Submitted by Joanne Stewart / Hope College on Thu, 03/31/2022 - 17:07
Description

This LibreTexts module by Dr. Tom Neils and Dr. Stephanie Schaertel provides a clear and thorough explanation of why some biochemistry and organic chemistry textbooks get the pKa of water wrong. The pKa of water at 25 ºC is 14.0 and not 15.7. This module describes the derivation of the correct value and describes why the value of 15.7 should not be used. 

VIPEr nanoCHAt : NeWBiEs Spring 2022 Learning Objects

Submitted by Shirley Lin / United States Naval Academy on Wed, 02/02/2022 - 18:07

This collection accompanies the IONiC VIPEr nanoCHAt video series NeWBiEs, recorded in Spring 2022. This series is comprised of weekly conversations with two IONiC members, Wes Farrell and Shirley Lin from the US Naval Academy, as they taught a foundation-level inorganic chemistry course for the first time. The LOs discussed in the videos are included in this collection.

An editable Review Jeopardy game via a Macro Powerpoint

Submitted by Paul Smith / Valparaiso University on Wed, 08/04/2021 - 23:17
Description

In searching for a way to review topics before exams, I was informed about this powerpoint template which is macro'd to be operated as a realistic Jeopardy game. The site for the original author of the macro is:

https://sites.google.com/site/dufmedical/jeopardy

(Jeopardy for PowerPoint by Kevin R. Dufendach is licensed under a Creative Commons Attribution 3.0 United States License.)

SLiThEr #23: "Strategies to Pre-assess First-year STEM students"

Submitted by Kyle Grice / DePaul University on Sun, 07/25/2021 - 15:30
Description

This is our 23rd SLiThEr. The collection can be found here. 

This discussion focused on ways to assess readiness for the general chemistry course sequence.

The YouTube video link for SLiThEr #23 is below under "Web Resources"

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).