HS-PS1-7 Mathematical Representations

Mole Unit Mini-Practicums

We all know how fundamental the mole concept is for stoichiometry. This year I brainstormed ways to really make it stick. I decided to do multiple mini-practicums, one for each learning target of the mole unit. I am sharing brief descriptions of the mini-practicums I did for each learning target.

Review Lab - Better than a Worksheet

It can be difficult to engage students in reviewing for semester exams by using worksheets or practicing problems on the whiteboard. If you are looking to change up your review plans, you might consider using a lab activity that provides opportunity to revisit many of the topics that need to be covered.

Determination of Citric Acid in Candies

Looking to change up your titration lab? Citric acid is very common in candy and other foods. Students will be engaged in using titration to find the amount of the acid in Mentos Now or other candy. Student and teacher documents are provided to help you use the activity with your own students.

Teaching Moles through Beans

The concept of the mole has always been a challenging topic for myself and my students. The challenge comes in part when we try to imagine 6.02 x 1023 of anything. Another challenge for some students is the math and theory behind this number and concept. I have tweaked an activity to help guide my students to an understanding of these concepts.

Increasing Access to Stoichiometry Through Differentiated In-Class Practice

In a recent post, I shared sample quiz questions as to how I have differentiated assessment within the mole unit. Here, I share a specific multi-day sequence within the stoichiometry unit. I have written extensively about the project that drives this unit (within the following blog posts: Why consider trying project based learning?, Backwards planning your PBL unit -­ An Overview of an Entire Unit and What ARE my students actually learning during this long term project (PBL)?), but very little about specific learning tasks. Below is a two day sequence of stoichiometry practice that I set up in my classroom. Stations are set up around the room and students rotate as necessary.

Balancing Equations with Molecular Models

I am a very firm believer that the world of physical science can be visualized and is an excellent medium for teaching students to model and to picture what happens at the molecular level. The first topic we decided to explore was balancing chemical equations. This seems like such a simple topic to chemistry teachers but I have found that it can be quite challenging for many of my inner city students. The first thing they ask me for is a list of rules that they can follow. We can discuss the problems of algorithmic teaching in a later post! For the time being let’s talk about how to get students to understand why they need to balance equations and discuss what we can call “Conservation of Atoms”.

Rethinking Stoichiometry

Stoichiometry is arguably one of the most difficult concepts for students to grasp in a general chemistry class. Stoichiometry requires students to synthesize their knowledge of moles, balanced equations and proportional reasoning to describe a process that is too small to see. Many times teachers default to an algorithmic approach to solving stoichiometry problems, which may prevent students from gaining a full conceptual understanding of the reaction they are describing. 

Building Molar Mass

An advantage to teaching on the trimester schedule allows me the opportunity to teach the same course again roughly twelve weeks later. So after grading my 2nd trimester students’ Chemistry B final exams, I was able to evaluate certain topics that caused my students problems, reflect on my teaching, and then determine how I was going to better prepare my students in the 3rd trimester chemistry B class.