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Fun with Formula Stoichiometry: “Who poisoned Veronica Merriweather?”

Chris Vyhnal | Fri, 09/16/2022 - 09:47

"Who Poisoned Veronica Merriweather?" is a fun application of formula stoichiometry for students who are placed in the role of a CSI lab sleuth helping to interpret chemical data to identify a murderer. Topics covered include formula stoichiometry, percentage composition, empirical and molecular formulas and gas chromatography–mass spectrometry.

The Empirical Formula of Magnesium Oxide Lab: A Successful Failure, Next Steps—and an Important Lesson

Michael Jansen | Mon, 08/16/2021 - 16:01

Michael Jansen reflects on a very common empirical formula lab that asks students to determine the empirical formula of MgxOy. He then explains how he continues to use it as a "successful failure", how he demonstrates an alternate procedure and leads his students to an important lesson.

An Upcycled Teaching Aid for Ionic Formulas

Jerry Godbout | Sun, 09/13/2020 - 19:15

Determining the empirical formulas of ionic compounds based on charge balance is often a challenge for beginning chemistry students. Many visual aides have been developed for this purpose, from repurposing commercial interlocking bricks to custom 3-D printed bricks. This article describes yet another option– upcycled can carriers.

Nomenclature

Chad Husting | Mon, 11/27/2017 - 18:25

Nomenclature is a tough topic. I tell students that we are living in the land of symbols while we study nomenclature. It is important but it is difficult to get them excited. I started fishing for resources. The American Association for Chemistry Teachers (AACT) has been a great resource to help me try new things.

Chemical Formula Challenge

Doug Ragan | Thu, 03/23/2017 - 08:11

According to the app store description, Chemical Formula Challenge is "An educational game to improve your ability to form chemical formulas from chemical names. You can either play it yourself or challenge a friend". The app features different levels of play such as easy, normal, and hard regarding the difficulty of the ions. As an example, beryllium chloride is considered "easy" while lead II nitride is considered "hard". The app then gives the user several ions to choose from and the user must then select the correct number of ions needed to balance the formula correctly.

Cookbook to Inquiry....Another Attempt

Chad Husting | Sun, 10/25/2015 - 19:32

There is a hydrate lab which is done by many teachers. Typically, students first use a known hydrate and are provided the formula.  As an example, they might use CuSO4 . 5H2O.  On paper, they would work through the percent by mass of water in copper (II) sulfate pentahydrate.  They then would be given a mass of the copper (II) sulfate pentahydrate, calculate how much water they should lose and then they would heat it and compare the data with the calculated value. Next, they are given an unknown hydrate.  They are also given the molar mass of the unknown salt of the hydrate and they have to calculate the molar ratio of salt to water based on their data.  Here is one possible way to “tweak” this lab.