20 DIY Science: Illustrated Guide to Home Chemistry Experiments
of solution, but that’s no problem. For example, if I make up 500
mL of 1 M hydrochloric acid, I simply store part of it in a 4-ounce
bottle and the remainder in a pint bottle, from which I refill the
smaller bottle as needed.
Every bottle should be labeled indelibly with its contents. If you’re
patient and want to do things the traditional way, you can use an
oilstone or whetstone to frost an area on a glass bottle that can
then be labeled with a marking pen or wax pencil. I prefer to use
my laser printer to print sheets of sticky labels, which adhere
quite well to glass and plastic bottles. After applying the label,
I cover it with clear tape to protect it. It’s also fine to hand-label
bottles, as shown in Figure 3-11, as long as you print neatly and use
an indelible marking pen. Include at least the name of the chemical
and, if it’s a solution, its concentration. Many reagents have limited
shelf lives, so date the bottle when you make up the contents.
BARNES BoTTLES
A Barnes bottle is a dropping bottle that is used to store an
indicator or another solution that is typically used drop-wise
in small quantities. The rubber bulb of the dropper in a Barnes
bottle is large enough to plug the mouth of the bottle. When you
need a few drops of the solution contained in the Barnes bottle,
you remove the dropper, dispense the solution, and then reinsert
GASSNL A d STRoNG BASES doN’T mIx
Although glass is impervious to most solutions used
in a home chem lab, an exception is concentrated
solutions of strong bases, such as sodium hydroxide and
potassium hydroxide. These solutions literally dissolve
glass, given enough time. Store concentrated base
solutions in plastic bottles that are rated for use with
strong bases.FIGURE 3-11: Make it a habit to label and date all storage bottles
the dropper in the bottle, which seals it. It’s handy to have half a
dozen or so Barnes bottles on hand, filled with phenolphthalein
and other indicators, dilute acids and bases, and so on. You can,
of course, substitute any dropping bottle that you recycle from
the bathroom or kitchen.wASH BoTTLES
A wash bottle is a soft plastic bottle that allows you to dispense
a liquid through a tube in a fine stream by squeezing the bottle.
Washing bottles are used for rinsing glassware, adding small
amounts of liquid to a reaction vessel in a controlled manner, and
so on. You’ll want at least one washing bottle, filled with distilled
or deionized water for general use around the lab. You may
want additional washing bottles to contain alcohols and other
commonly used liquids. Note that washing bottles are designed
to dispense liquids, but are not intended to be used for long-term
storage. An empty, thoroughly washed shampoo bottle with a
squeeze top is an adequate substitute, as is a boutique spring
water bottle with a squeeze top.MSCELLAI nEOUS GEnERAL GLASSWARE
In addition to the test tubes, beakers, flasks, bottles, and other
general glassware, a well-equipped lab requires an assortment of
miscellaneous glassware.FIGURE 3-12: Barnes bottles FIGURE 3-13: A wash bottle