CHAPTER 1 Safety in the laboratory classes a) General Instructions: There are some general instructions in safety precautions in the laboratory work. Most accidents could be prevented if proper precautions are taken. The attention, honest and careful work is required from students. They should therefore perform only those experiments that are selected for them by teacher. Such experiments are sate and the students do not have to worry. Nevertheless even a very simple error can produce dangerous conditions for the work. Sometimes, even a slight change of concentration of one reagent is sufficient to change the safe conditions of a chemical reaction (and to cause an explosion). The reaction then might occur in a different way, perhaps at a highly accelerated rate. Therefore students are asked not to deviate from the procedure in the manual. b) Accidents; The most common accidents occur when students try to insert tubing, a thermometer, or a glass rod into a hole in a rubber stopper. Other frequent sources of danger are volatile organic liquids that might ignite if students bring open flame close to them. We should know what to do if somebody spills a caustic reagent on oneself or if some chemicals %o\ into one's eye. The chemical substance in the eye has to be handled with water from' the nearest sink, at least 10 minutes, and we call the doctor immediately. We should also know what to do if the fire breaks out in the lab, which means to use an extinguisher or sand, blanket, or anything appropriate at the time. Every student must always know where water, shower, first-aid kit, fire extinguishers and other things are so that he / she will not have to look for them long if they are needed quickly.- ------ , Chemical glassware: Erlenmeyer Flasks Round Flat-Bottom Flasks Round-Bottom Flasks Beakers Test Tube Round-Bottom Flask with Three-Neck Vertical Septum Inlet Round-Bottom Flask DO g Funnel Rubber Büchner Funnel Stoppers Glass Stoppers Filtering Flasks Volumetric Flasks with stoppers Separatory ^ Funnels Dropping Funnels Vacuum-Distilling Claisen Adapters Thermometers Straight Connecting Onset Three-Way Reducing Adapters Adapters Adapter Adapter Pipettes Condensers Burette -19- Distillation Cooling water flask Receiving flask Vocabulary 1: alteration adapter beaker blanket blender bottle bottom burette burner calcine calcining circle ceramic clamp (holder) combustion spoon condenser conical container cork crucible crucible tongs desiccator dish distillation evolve extinguisher filtration fire extinguisher flask fluid fume chamber funnel gauze glass rod glass stopper glassware graduation heating ignite insert layer lid liquid melt mixer mortar neck opening V*te/i změna rozdvojka, nástavec, adapter, redukce kádinka deka, přikrývka; plášť; povlak kuchyňský mixer láhev T dno byreta hořák žíhat, pražit žíhací kruh keramický držák spalovací lžíce chladič kuželovitý, kónický nádoba, bedna, kontejner korek taviči kelímek kleště na kelímek sušička, exsikátor miska destilace kapací vyvíjet hasicí přístroj filtrace hasicí přístroj baňka, láhev tekutina digestoř trychtýř, nálevka síťka skleněná tyčinka skleněná zátka laboratorní sklo dílkování, stupnice zahřívání zapálit, zahřívat vložka; vložit, vsunout vrstva víko, víčko kapalina tavit, rozpouštět míchačka třecí miska krk; hrdlo láhve otvor pinchcock pipette pour powder funnel . • reagent round rubber stopper secure separation separatory septum inlet solvent spirit burner stopcock straight sublimation