## Bell Ringers for Conservation of Mass

Bell Ringers related to the Law of Conservation of Matter.

Amy Zitzelberger | Thu, 10/01/2015 - 12:22

Bell Ringers related to the Law of Conservation of Matter.

Doug Ragan | Sun, 05/10/2015 - 21:27

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 2^{nd} 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 3^{rd} trimester chemistry B class.

Dan Meyers | Fri, 12/12/2014 - 11:34

This is a Chemical Reactions lab that I modified to meet NGSS guidelines.

David Licata | Sun, 11/16/2014 - 20:30

This article describes a three week lesson plan for teaching stoichiometry using an algorithmic method. Two labs (one designed as a laboratory quiz) several cooperative learning exercises, student worksheets and guided instructional frameworks (forcing students to develop good habits in writing measures and doing problem solving) are included. The highlight of the lessons is the "chemistry carol" (based on Felix Mendelssohn's music for "Hark! The Herald Angels Sing") in which students recite a five-step algorithm for completing stoichiometry problems.

David Licata | Sat, 11/15/2014 - 23:01

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.

David Licata | Sat, 11/08/2014 - 21:40

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.

David Licata | Wed, 11/05/2014 - 19:52

This worksheet asks students to do basic conversions of mass or molecules to moles and *vice versa.*

David Licata | Tue, 11/04/2014 - 20:09

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.

David Licata | Mon, 11/03/2014 - 21:39

Given the amount of one reactant, students must use stoichiometry to find the ideal amount of the second reagent to use to create purple fireworks. The teacher ignites each groups' fireworks. Ideal mixture create little or no ash. Student assignment sheet with directions (and different initial amounts) plus teacher information and sample answers are included. This is an exciting and engaging activity that can be used as a stoichiometry quiz.

David Licata | Wed, 10/29/2014 - 21:41

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.