See if anybody else at your bench or in the lab needs

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: rtion of a reagent to its original container. See if anybody else at your bench, or in the lab, needs it. If not, give it to your instructor, who will look at you in a forlorn and sullen manner but will appreciate that you did not put it back in the original container. Returning unused portions of reagent greatly increase the odds of cross contamination, that is, getting the reagent contaminated with an unwanted chemical. (7) NEVER pour a waste chemical in the drain, or put it in the garbage, unless otherwise instructed to do so by your lab supervisor. Waste bottles will be provided. Always pour waste into the appropriate and labeled waste bottle (reading the waste bottle label twice). (8) If you have glass stirring rods or glass tubes with sharp or jagged edges, fire polish them. This means holding the sharp end in a Bunsen burner flame and rotating the rod or tube until a bright orange flame begins to show on the end being heated. Continue to heat while rotating another minute or so, effectively melting that end a little bit. Be SURE to let it cool COMPLETELY before attempting to fire polish the other end. Dakota State University Page 13 of 232 Safety Guidelines General Chemistry I and II Lab Manual (9) Many items (glass, metal, etc) look exactly the same HOT they do cool. Be VERY careful whenever working with flames that ALL of your equipment (beakers, flasks, ring stands, etc.) are cool before handling them. (10) If you are inserting glass tubing into a rubber stopper, use the following technique to avoid jamming a jagged piece of glass through your hand; (1) use glycerol or water to lubricate either the end of the glass tubing being inserted, the hole in the stopper the tubing will be inserted into, or both; (2) protect your hands by using a paper towel to hold both the glass tubing as well as the rubber stopper; (3) hold the rubber stopper in such a way that the tubing cannot go through the hole and into your palm (your fingers should actually curve, holding the edge of the stopper, as if to make the letter "C"); (4) hold the glass tubing, also with your palm away from the end, near the end being inserted into the rubber stopper; (5) insert the glass tubing with a twisting motion; (6) clean up any excess glycerol; and (7) live your life free from scar tissue on your palms that everybody for the rest of your life will ask about by saying "how did that happen?", to which you will have to reply that you didn't listen to your dedicated and caring chemistry professor. (11) Improper heating of a test tube can result in the chemicals within the test tube shooting out, possibly resulting in injury to anybody in the path. When heating a test tube, use the following procedure; (1) unless directed otherwise, always place a few (five or six) boiling chips in the test tube; (2) use a test tube clamp to hold the test tube; (3) hold the test tube at about a 45o angle; (4) be sure the opening of the test tube is pointing away from anybody else (preferably towards a wall in a low-traffic area of the lab); (5) NEVER heat the bottom of the test tube (unless otherwise directed); instead heat the middle of the test tube just at the level of the liquid in the test tube; (6) move the test tube horizontally back and forth across the flame to prevent the liquid from heating too quickly; (7) should the liquid begin to overheat (heat too rapidly), remove the test tube from...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online