Using a Beral pipette to bring the water mass up to 100.00 g

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Everyone rightly treats strong acids with great respect, but many students handle strong bases casually. That's a very dangerous practice. Strong bases, such as solutions of sodium hydroxide, can blind you in literally seconds. Treat every chemical as potentially hazardous, and always wear splash goggles.

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MAINTAINING A LABORATORY NOTEBOOK

A laboratory notebook is a contemporaneous, permanent primary record of the owner's laboratory work. In real-world corporate and industrial chemistry labs, the lab notebook is often a critically important document, for both scientific and legal reasons. The outcome of zillion-dollar patent lawsuits often hinges on the quality, completeness, and credibility of a lab notebook. Many corporations have detailed procedures that must be followed in maintaining and archiving lab notebooks, and some go so far as to have the individual pages of researchers' lab notebooks notarized and imaged on a daily or weekly basis. If you're just starting to learn about chemistry lab work, keeping a detailed lab notebook may seem to be overkill, but it's not.

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CHEAPER BY THE POUND

Do not overlook the advantages of banding together with other home schoolers or like-minded hobbyists to buy chemicals in bulk. For example. a vendor may charge $3 for 25g of a particular chemical. $5 for lOO g, and $9 for 500 g. If you need only small amounts of chemicals, you may be able to cut your chemical costs dramatically by arranging with other homeschooling families or hobbyists to order chemicals in larger quantities and divide them among you.

The cost advantage is particularly great for chemicals that incur hazardous shipping surcharges. For example, if you order 100 rnL of concentrated nitric acid for $5. the vendor may add a $35 hazardous material shipping surcharge, for a total of $40. But if you order a 500 mL bottle of concentrated nitric acid for $15, the same surcharge applies, for a total of $50. If you divide that chemical with four friends. each of you gets 100 mL of concentrated nitric acid for only $10.

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MICROSCALE EQUIPMENT

The recent trend in chemistry labs, particularly school and university labs, is to substitute microscale chemistry equipment and procedures for traditional semi-micro or macroscale equivalents. Microscale chemistry, often called microchemistry, is just what it sounds like. Instead of using standard test tubes, beakers, and flasks to work with a few mL to a few hundred mL of solutions, you use miniaturized equipment to work with solution quantities ranging from 20 pL (microliters, where one pL equals 0.001 mL) to a couple mL.

Using microscale equipment and procedures has many advantages. Microscale equipment and procedures are less expensive than standard equipment and procedures, which is a major reason for the popularity of microscale chemistry. Using microscale equipment and procedures means that chemicals are needed in very small quantities, which are safer to work with and easier to dispose of properly. Microscale also makes it economically feasible to do experiments with very expensive chemicals, such as gold, platinum, and palladium salts. Setup and teardown is faster, allowing more time for actual experiments, and cleanup usually requires only rinsing the equipment and setting it aside to dry.

Against these advantages, there are several disadvantages to microscale chemistry. First and foremost, everything is on such a small scale that it can be difficult to see what's going on. For example, you may need a magnifier to examine a precipitate (or even to determine whether there is a precipitate). Because of the small scale, measuring or procedural errors so small that they would have no effect on a traditional scale experiment can greatly affect the outcome of a microscale experiment.

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PROTECTING WORK SURFACES

Some of the chemicals you work with may stain or otherwise damage wooden or laminate work surfaces. I protect my work surfaces, which are standard kitchen laminate counters, by covering them with rubber nonslip mats that are available in various sizes and thicknesses at craft stores. I also put an old bath towel between the counter top and the rubber mat. The mat provides a smooth. level, chemical-resistant work surface, and the old towel absorbs any liquids that run off the mats.

My advisor. Dr. Mary Chervenak, is an expert on paints and coatings. I asked her and my other advisor. Dr. Paul Jones. if there was any kind of paint that could be used to protect surfaces from most laboratory chemicals. The short answer is "not really." Standard latex, polyurethane, and epoxy-based paints and coatings offer reasonablv good protection against many reagents and solvents. including the dilute reagents used in most of the experiments in this book. However, they offer less (or no) protection against strong acids or bases or some organic solvents.

Still, as Dr. Jones commented, some protection is better than none, and in a sense you can think of these pints as ablative coatings. The coating itself may dissolve in or be eaten away by a strong chemical. but it may protect the underlying surface long enough for you to dilute, mop up, or neutralize the spill. It I used a wooden workbench or a similar surface. I'd put several thick coats of an epoxy-based deck or floor paint on it. and then protect it further with a rubber mat and towel.

Even if you take reasonable precautions and work carefully, it's almost inevitable that at some point you'll spill something nasty on your work surface. That's a good argument for choosing a work surface that's expendable. If you eat holes in a sheet of plywood or particle board, that's cheap and easy to replace. If you eat holes in your washer/ dryer. you may have some explaining to do.

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Chemical incompatibility matrix

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WHO THIS BOOK IS FOR

This book is for anyone, from responsible teenagers to adults, who wants to learn about chemistry by doing real, hands-on laboratory experiments.

DIY hobbyists and science enthusiasts can use this book to master all of the essential practical skills and fundamental knowledge needed to pursue chemistry as a lifelong hobby. Home school students and public school students whose schools offer only lecture-based chemistry courses can use this book to gain practical experience in real laboratory chemistry. A student who completes all of the laboratories in this book has done the equivalent of two full years of high school chemistry lab work or a first-year college general chemistry laboratory course.