tube from apointmore than2 inches away from thestopper.Otherwise, the
weightofthestopperwill make the tube snap. If thetubingis partof a funnel or
thistle tube, do not hold it by the funnel for the same reason.Handlethermom-
eters the same way, too.
Never use a chemical thatis not labeled.Itmight bepoisonousor cause a
violent anddangerousreaction. Neverreturnunused chemicals to their original
bottles. You may causecontaminationor make anerrorthatwill spoilfuture
experiments. Throwthe unused chemical away in theproperwastecontainer.
Only wastepaperbelongs in thewastepaperbasket. Putdiscardedsolid chemi-
cals in anearthenorpotteryjar.Lateryou should wrap them innewspaper
andthrowthem in anincineratororgarbagecan. Put liquid wastes into a sink
partlyfilled with water, and then wash them away with the tap water running
for at least 5 minutes. This will dilute themandlessen the effect they might
otherwise have on theplumbing.
Never taste or smell a chemical directly.Do not do so at all unless the experi-
ment directs you to.To taste a chemical, transferI dropto your tongueby
means of a glass rod. Wash your mouthout immediately with water. To smell
a chemical, fan thevaportowardyour nose with your hand.Bepreparedto
turnyour head away quickly if theodorproves to beirritating.