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Off the Shelf Chemistry
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OBJECTIVES1. The student will learn that chemicals are not something just found in laboratories. Our physical environment is composed of chemicals. Our bodies are composed of chemicals. Understanding the principles of chemistry helps us better understand our world. 2. The student will learn to read and understand the ingredient labels on consumer products. In doing this the student will become a more sophisticated consumer. 3. The student will be able to use both English and SI systems of weights and measures to conduct experiments and to compare different brands of similar products. 4. The student will learn the importance of making and recording accurate observations. 5. The student will learn that in science, language is very important. Terms must be carefully defined in order for scientists to communicate with each other. The student will learn the difference between operational definitions and conceptual definitions. 6. The student will develop an appreciation of the chemistry that is used in our everyday lives.
GENERAL PROCEDURESThis chemistry lab manual is designed to use consumer products for student chemistry experiments. The students should be required to shop for many of the reagents. They will need to carefully read the labels of the products. They will develop greater understanding with experience. As they develop the good habit of reading the fine print on the ingredients portion of the label, they will be more confident of their ability to make informed intelligent choices. Safety: All standard chemistry lab safety procedures must be strictly followed. The instructor must carefully check the labels on all the products used in the labs. The formula of a product and the chemicals used in a product can be changed by the manufacturer at any time. Obtaining the Chemicals: Here is a list of where the chemicals for the experiments may be purchased. All of the reagents for these experiments may be purchased in supermarkets, drugstores, paint stores, etc., except chemical indicator solutions. No Lab Tables Required: These experiments are especially suited to schools that have intensive scheduling. The experiments are designed to use a minimum of laboratory equipment so that they may be carried out on tables in a standard classroom if necessary. This allows the students to do hands on lab work without being in the chemistry lab. The emphasis is inquiry. The students must do more thinking and will not be able to look up answers to complete the laboratory reports. This makes these experiments more challenging than they may appear at first glance. Background Information: As in any scientific endeavor, the first step is to gather information about the subject. Before each experiment, the students need to have information relevant to the lab topic. The PRE LAB DISCUSSION provides some background information. The teacher may wish to provide additional information or the students may look up additional relevant information. Language Skill Building: Clear precise communication is a key to good science. Scientists must be able to communicate their findings in unambiguous language. This often means that the common words are defined as used in this report so that the reader knows exactly what the scientist means when he reads the term. The teacher may wish to discuss the term significant as it is found in many scientific studies. It is usually defined using a statistical test in a scientific study but it shows up in advertising without any definition. Scientific writing is designed to have only one interpretation while poetry will invoke many different meanings, depending on the reader's personal experiences. Students often tell the teacher that they "know" something but can't put it into words. Developing language skills is a large part of science, and students must be taught how to better use their language to communicate their ideas. The first step is to have students clearly define the terms that they are using. In many experiments, the students need to develop operational definitions for terms that are needed to describe critical aspects of the experiment. Scientific Thinking: The students must develop confidence in their own THINKING ability. Great science does not depend on expensive complex equipment but on the clear thinking of the experimenter. The experiments in this manual serve only as entertainment if students do not do the follow-up THINKING SCIENTIFICALLY. Teachers should insist that students think before they write and that they express their thoughts clearly. Printing the Labs: The labs are available both as Web pages and as Adobe Portable Document Format (PDF) files, a more printer-friendly format. You must have Adobe Acrobat Reader installed on your computer to use this feature. You can download the free Adobe Acrobat Reader software here.
EXPERIMENTS1. Introduction to AlchemyLike the alchemists, our objective is to make gold from base metals; we use drain cleaner, pennies and galvanized nails. PDF lab for Introduction to Alchemy 2. Water, Water Everywhere DifferentTo determine the differences between samples of water obtained by the class. PDF lab for Water, Water Everywhere Different 3. A Slippery Slimy SubstanceTo make and study an unusual polymer, using Borax, guar gum and food coloring. PDF lab for A Slippery Slimy Substance 4. What is the Pop in Popcorn?To determine what causes some corn kernels to POP when heated. PDF lab for What is the Pop in Popcorn? 5. Hard Rock CandyTo study how crystals form while making sugar crystal rock candy. PDF lab for Hard Rock Candy 6. Heat -- Hide & SeekTo learn the difference between heat and temperature, using moth crystals. PDF lab for Heat -- Hide & Seek 7. Hot & Cold ReactionsTo explore the energy of chemical reactions, using baking soda, lye, vinegar, zinc, HCl. PDF lab for Hot & Cold Reactions 8. Are We Saturated Yet?To make and observe the properties of unsaturated, saturated, and supersaturated solutions, using photography fixer. PDF lab for Are We Saturated Yet? 9. Cleaning Up Your ActTo make a useable soap. PDF lab for Cleaning Up Your Act 10. The Solution to Solubility is the SolventTo determine the solubility of three general types of common solvents: water, alcohol and xylene. PDF lab for The Solution to Solubility is
the Solvent 11. Out Spot, Darn SpotTo explore the science of laundry. This laboratory exercise is different from the others in that students will not be given a set procedure to follow to remove a spot. Instead they will need to use the information provided to develop a procedure to remove a spot. PDF lab for Out Spot, Darn Spot 12. Can the Mettle of Metal be Improved?To determine the effects of annealing, quenching, and tempering on metals, using bobbi pins, hair clip, single strand steel wire. PDF lab for Can the Mettle of Metal be Improved? 13. Creepy MetalsTo determine the tensile strength and creep in three common metals. PDF lab for Creepy Metals 14. Blowing Up Balloons, ChemicallyTo determine what observable factors are changed in a chemical reaction and what factors remain constant. PDF lab for Blowing Up Balloons, Chemically 15. AntacidsTo determine the amount of acid neutralized by several brands of antacid tablet. PDF lab for Antacids 16. Chemistry Clicks Your BICTo experimentally determine the molecular mass of butane, using a lighter. PDF lab for Chemistry Clicks Your BIC 17. Electric Gel CellTo make functional electrical cells and determine the relative strength of each type of cell, using Jell-O. PDF lab for Electric Gel Cell 18. Viscosity is a VirtueTo compare the viscosity of motor oil at different temperatures; compare the viscosities of several grades of motor oil; and to compare the viscosity of new and used motor oil. PDF lab for Viscosity is a Virtue |
© 1999 Robert Farber - All rights reserved. Teachers are encouraged to copy and modify these labs for use in their teaching. Please send any questions or comments to Robert Farber (robtfarber@verizon.net).