Each spring my Local Section of The American Chemical Society (ACS) hosts a rigorous two part exam as part of the selection process for the The International Chemistry Olympiad (IChO). The lab practicals on the exams are presented as problems. No procedure is given. Students must use their chemistry knowledge and lab experience to devise a plan and solve the problem. The best part is that the released exams come with lists of materials and equipment, helpful hints to the proctors, and solutions! This is a great source for Inquiry-Based Lab Practicals.
Laboratory Assessments and Resources
Flinn Scientific has a great elearning video series. Many of the videos have master teachers demonstrating some great labs and techniques that they do in the classroom.
Students who are tired of "pen and paper" work now get to get up and use their answers to mass something or find the volume of something and see if they are correct.
Think it’s possible to get nostalgic over paperwork? I just did, spurred by editor-in-chief Norb Pienta’s editorial Thinking about Champions in the December 2015 issue of the Journal of Chemical Education.
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.
At Chem Ed 2015, a teacher from Texas showed me this quick and dirty way to do a distillation that the kids can do. I forgot her name. "Lady from Texas", let me just say "thank you". If you are reading this, please shoot me an email and I will be more than happy to give you credit. It worked really well.
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.