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”.
For my students and me, the AP Chemistry exam does not mark the end of the school year. Once the AP exam is over, my students are exhausted but our class continues to meet for three more weeks. Each year we complete a qualitative analysis lab, but this year we finished earlier than I anticipated. For the first time all year, I have the luxury of time.
During the first week of school, I welcome my students to the What Not To Do Lab. I use the cartoon activity to review their Safety Contract handout from the night before. With more than 30 safety violations shown, the cartoon serves as a great ice breaker as I have each student introduce themselves and then list a safety infraction being shown on the cartoon.
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.
This worksheet is intended to be used as a "Guided Instructional Activity" (GIA). Students read a statement that gives a either a conversion factor or a pair of related measures and then write the information as two equivalent fractions ("conversion factors") and as an equality. In each representation, students are directed to give the numeral of the measure, unit, and identity of the chemical.
This set of three worksheets are intended to be used as collaborative "Guided Instructional Activities" (GIAs). Two students cooperate to complete the steps of a stoichiometry problem, alternately doing parts of the process as they explain what they are doing and evaluate their partner's work.
The three "Guided Instructional Activities" in this activity are three cooperative learning pieces in which students are guided through the process of converting from one unit to moles (or moles to a unit) by the method of "unit analysis" (dimensional analysis). Students alternate steps in the process and evaluate the success of each step.
This worksheet is intended to be used as a "Guided Instructional Activity" (GIA). It asks students to find the molar mass of selected elements and write the molar mass as two equivalent fractions ("conversion factors") and as an equality. It is designed to help develop good habits in representing molar mass and other conversion factors, and to emphasize the idea that a conversion factor has a numerator and denominator that "name" identical quantities using different measures.
Students combine sodium carbonate and hydrochloric acid generating carbon dioxide gas which is allowed to escape. They measure the actual yield of carbon dioxide produced (missing mass), calculate the theoretical yield using stoichiometry, and then the percent yield. Students understand that 100% yield is the most appropriate answer (based on the Law of Conservation of Mass), so after considering the meaning of significant figures and the uncertainty of their measurements they are asked to decide if they did (or did not) get an answer that might indicate the validity of the Law.
Make ice cream in a baggie to emphasize energy changes, direction of energy transfer, dissolution and colligative properties.