Chemistry
__
We are strong believers that chemistry is best learned by actually doing it. We also know that many schools do not have specialized lab facilities for teaching chemistry to all students. Many schools are prohibited from using toxic or hard-to-dispose chemicals. Many
schools may not use open flame in a classroom. Despite the legal and environmental restrictions we believe that chemistry can and should be taught in a hands-on, laboratory based way. It just takes a lot of rethinking what experiments to do. It also requires designing some unique lab apparatus that makes hands-on, quantitative chemistry accessible to all students even without gas jets, or fume hoods.
We believe students learn more by investigation than they do in formal experiments. While we encourage that students do a few formal lab reports, most of Laboratory Investigations Manual is just what the title says: investigations. There is no formal hypothesis because these sorts of investigations are what humans do when they are learning enough to make a sensible hypothesis. |
Making connections
Students remember chemistry concepts better if they can see the connections between classroom materials and the physical world that they experience every day.
Investigations often begin with questions as seemingly simple as, “Why does a green object appear green to the human eye?” The Lab-Master includes an RGB spectrophotometer that allows students to take absorbance measurements. They explore the qualitative and quantitative relationships among light, color, and absorbance. In addition, they are prompted to research why digital displays use the RGB system whereas printers use CMYK colors. _
Students walk away from the investigation knowing that colors they see around them result from the way materials absorb and reflect white light.
|
Hands-on learning
_
The periodic table of elements lists atomic masses as “averages.” How do we explain this to students? How do we teach isotopes in a way that is meaningful to them? In A Natural Approach to Chemistry students use an atom model and see for themselves how electrons, protons, and neutrons are organized inside any atom of any element. The relationship between neutrons and isotopes becomes crystal clear, and students now understand where the term “average” in “average atomic mass” comes from.
Energy levels can be an elusive concept for students. Using the atom model, students physically place electrons into the correct “quantum states.” Using this hands-on method of learning, they actually apply the Pauli exclusion principle and learn to write electron configurations. |
Safety and effectiveness
_
We have created investigations that do real chemistry without toxic chemicals or chemicals that are considered hazardous waste. Virtually every experiment can literally be safely poured down the drain. There are no fume hoods. All the experiments can be done in open air.
There are no open flames. The Lab-Master unit includes a clever test tube heater that can boil 30 mL of water in 3 minutes and can be left on safely all night or longer. Even better, it gives you precise temperature control from room temperature up to about 150oC. Safety does not compromise the effectiveness of the instruction. Each investigation teaches key chemistry concepts from stoichiometry to redox reaction, to reaction rates, to calorimetry. |
_
A. Investigation 11B:
Students explore stoichiometry and percent yield using a quantitative analysis of the formation of copper(II) carbonate (CuCO3). B. Investigation 12C: A chemical equilibrium is a dynamic process. Students vary experimental conditions and witness LeChâtelier’s principle in action. C. Investigation 13B: Using a titration procedure, students determine the acetic acid (C3COOH) content in commercial vinegar. D. Investigation 15A: A lemon can really act as a battery and light an LED! In studying redox reactions, students explain how chemical reactions can generate electricity. |