Use of Reagent Bottle

Clear and amber reagent bottles are the most common. Amber bottles protect the contents from light while clear bottles are ideal for displaying items. The sizes range from 30 ml (1 ounce) to 20000 ml (about 5 gallons), and the larger ones can be used in the lab to store preserved biological specimens. The larger ones are also great for terrariums or miniature aquariums.
Because glass expands and contracts with temperature changes, care must be taken when heating and cooling reagent bottles. The neck of a reagent bottle expands when heated, allowing the tapered stopper to drop further into the bottle. When the bottle is cooled, the neck shrinks around the stopper, securing it. As the neck shrinks, the rough surface of the neck and stopper prevents the stopper from sliding up. If the temperature changes significantly enough, the bottle's neck can crack if it shrinks too tightly around the stopper. Furthermore, if hot liquid is poured into the bottle, the liquid forms an airtight seal between the stopper and the bottle, and as the liquid and steam in the bottle cool and shrink, the stopper is drawn down into the bottle neck. The same principle causes the center of a canning jar lid to pop down until the seal is broken.

When pouring hot liquids into a reagent bottle or storing it in the refrigerator, prop the lid open with a toothpick or other small object until the liquid and bottle are cool. Place a sheet of plastic wrap loosely over the bottle neck before pushing the stopper down to seal the bottle while preventing the lid from sticking.