vi.As the glass begins to slide into the rubber,move the hand holding the glass back a little,always keeping it no more than 1"from the rubber. vii. Most accidents occur because the glass snaps above the stopper from a force sideways(torque).Keeping your hand close to the stopper will help prevent your exerting a force sideways on the glass viii. The above considerations apply also to attaching rubber hoses to condensers. The condenser should be in your hand(not clamped to an apparatus)and gripped close to the lubricated connector being inserted into the hose c.Never use a thermometer as a stirrer!Always support a thermometer in a beaker or flask with a clamp.If a mercury thermometer breaks,immediately contact the laboratory instructor and restrict access to the area of contamination until cleanup can be arranged. d.Round-bottomed flasks will not stand upright by themselves and if rested on the counter will roll.They must be supported on a cork ring,in (not on)a beaker,or in a clamp. e.When glassware is assembled,care should be taken to use the minimum number of clamps needed for support,making sure: i.The clamp is attached to a vertical support bar. ii.No torque is applied by the clamp. iii. Top-heavy apparatus is prevented from rotating and tipping. iv. Hanging pieces are clamped-grease will not hold them against the force of gravity! f Do not use a glass stopper to seal a hot container or you may never get it out again. Cork is recommended for organic solvents since rubber dissolves in organic solvents and vice-versa g.Graduated cylinders are metastable and tip easily with the touch of a sleeve. h.Report breakage of glassware to your instructor for disposal instructions. i.Think before cleaning equipment-it makes little sense to scrub a graduated cylinder that contained ether or a water-insoluble material with soap and water. 4.Safety Equipment 66 vi. As the glass begins to slide into the rubber, move the hand holding the glass back a little, always keeping it no more than 1" from the rubber. vii. Most accidents occur because the glass snaps above the stopper from a force sideways (torque). Keeping your hand close to the stopper will help prevent your exerting a force sideways on the glass. viii. The above considerations apply also to attaching rubber hoses to condensers. The condenser should be in your hand (not clamped to an apparatus) and gripped close to the lubricated connector being inserted into the hose. c. Never use a thermometer as a stirrer! Always support a thermometer in a beaker or flask with a clamp. If a mercury thermometer breaks, immediately contact the laboratory instructor and restrict access to the area of contamination until cleanup can be arranged. d. Round-bottomed flasks will not stand upright by themselves and if rested on the counter will roll. They must be supported on a cork ring, in (not on) a beaker, or in a clamp. e. When glassware is assembled, care should be taken to use the minimum number of clamps needed for support, making sure: i. The clamp is attached to a vertical support bar. ii. No torque is applied by the clamp. iii. Top-heavy apparatus is prevented from rotating and tipping. iv. Hanging pieces are clamped - grease will not hold them against the force of gravity! f. Do not use a glass stopper to seal a hot container or you may never get it out again. Cork is recommended for organic solvents since rubber dissolves in organic solvents and vice-versa. g. Graduated cylinders are metastable and tip easily with the touch of a sleeve. h. Report breakage of glassware to your instructor for disposal instructions. i. Think before cleaning equipment - it makes little sense to scrub a graduated cylinder that contained ether or a water-insoluble material with soap and water. 4. Safety Equipment