Laboratory Procedures

Laboratory Procedures Chemistry

Fume Hood • Located between lab and prep room • Prevents harmful fumes from entering lab • May be used for demonstrations • Often used by teacher when diluting or disposing of chemicals • Open to outside at all times, fan can be turned on for more airflow Chemistry

Spill Control • If you spill on yourself, rinse with water immediately! • If you spill on the lab bench or the floor, dilute with water if practical before cleaning up. • Then use one of the following spill control products, all located under the goggle cabinet Chemistry

Spill Control • Spill control pillows: • Use for any spill • Place pillow on spill and wipe as needed • Sand • Use for any spill • Mainly for containment – keeps spill from spreading Chemistry

Spill Control • Absorbent material • Use for any spill • Very absorbent • Especially useful for flammable liquids • Ethanol, acetone, etc. • Acid neutralizer • Use for acid spills • It may foam Chemistry

Safety Shower • Located next to fume hood • Used for chemical spills over large areas of the body. • To use: • Stand under shower • Remove effected clothing • Pull down on handle • Push up on bar to shut off Chemistry

Eye Wash Station • Located under safety shower • Used for chemicals splashed in eyes • To use: • Push lever to turn on • Put eyes in path of spray • Hold eyes open • Remove contact lenses • Stay for 10 minutes Chemistry

Fire extinguishers • Located by lab door • Pull hard on door to open • To use, remember PASS • Pull pin out • Aim at base of fire • Squeeze trigger • Sweep from side to side Chemistry

Fire blanket • Located near fire extinguisher • Use to cover a person who is on fire • If you are on fire, • Stop, drop, and roll • Someone will get the fire blanket and help you Chemistry

Fire alarm • Located in hallway • Use if there is a large or uncontrolled fire • Pull alarm and exit the building Chemistry

Gas Shut Off • Located near prep room • Used to turn off gas to entire lab • Turn handle so it is perpendicular to pipe to shut gas off Chemistry

Lab attire • Goggles and aprons are designed to protect you from chemical spills – wear them • Take care to keep your hair and clothing away from chemicals and bunsen burners • Be careful with open-toed shoes and shorts or short skirts Chemistry

Use common sense • When in lab, pay attention to what you are doing • Watch where you are going • Don’t push, shove, pinch, startle, or sneak up on anyone • Don’t crowd around chemical or weighing stations – everyone will get a turn Chemistry

Test tubes • Available in many sizes • Used for many tasks, including mixing and heating of substances Chemistry

Test tube brush • Used to clean test tubes • Different sizes are available – ask if you need a different one Chemistry

Test tube holder • Used to hold test tubes in your hand while heating them Chemistry

Utility clamp • Used to hold test tubes or flasks attached to a ring stand Chemistry

Test tube rack • Sets on table • Used to hold test tubes during an experiment Chemistry

Ring stands and rings • Variety of uses • Often used to support test tubes, beakers, or flasks being heated by a bunsen burner Chemistry

Graduated cylinders • Available in different sizes • Use the smallest one that will meet your needs for the best accuracy • If measuring a large amount you may need to refill as you measure Chemistry

Beakers • Used to hold chemicals • May be used for mixing or heating • Only used to measure approximate volumes Chemistry

Erlenmeyer flasks • Used to hold, mix, and heat chemicals • To mix, hold by the neck and swirl Chemistry

Florence flasks • Used to hold, mix, and heat chemicals • To mix, hold by the neck and swirl Chemistry

Beaker tongs • Used to move hot beakers Chemistry

Forceps • tweezers Chemistry

Squares • Wire mesh and ceramic • Used to support beakers and flasks being heated with a bunsen burner Chemistry

Scoopula • Used to scoop dry materials out of their bottles Chemistry

Evaporating dish • Used for heating Chemistry

Watch glasses • Curved circular pieces of glass • Often used to cover evaporating dishes while heating Chemistry

Collecting bottles • Variety of uses • Often used to collect displaced gases Chemistry

Crucible • Used for heating • Has a lid Chemistry

Clay triangle • Used to support crucibles being heated by a Bunsen burner Chemistry

Crucible tongs • Used to move hot crucibles or crucible lids Chemistry

Pneumatic trough • Used to hold large quantities of liquids (usually water) • Has an overflow prevention spout: make sure this is over the sink Chemistry

Wash bottle • Squeeze bottle • Often used for cleaning • Never touch the tip of a wash bottle to anything. • After you stop squeezing, the bottle sucks in air. • If there is a chemical on the tip of the bottle, it will suck that in too. Chemistry

Hot glassware • Looks the same as cool glassware • If you drop hot glassware, don’t catch it with your hands!! • I would rather clean up broken glass than treat you for burns Chemistry

Broken glassware • Sweep the pieces up with the broom • Put them in the glass disposal box Chemistry

Measuring solids • Use a balance • Place your weighing paper or other container on the balance. • Push the ZERO button. • Make sure the balance reads zero before you start putting the material on it. Chemistry

Measuring solids • Add a little at a time so you don’t go over the needed amount. • If you get too much, don’t put it back in the bottle. • Give it to someone else who needs it • Or put it in the trash or waste beaker Chemistry

Measuring liquids • Unless the directions say approximately, measure with a graduated cylinder. • Use the smallest graduated cylinder that will get the job done – this will be the most accurate. Chemistry

Measuring liquids • Read the graduated cylinder at eye level. • Don’t hold it up to your eyes. • Bring your eyes down to its level by squatting or bending over. Chemistry

Measuring liquids • Pour slowly so you don’t get too much • Be extra careful if you are using a funnel • If you get too much, don’t pour it back in the bottle. • Give it to someone else who needs it • Or pour it down the drain with lots of water • Or put it in the waste beaker Chemistry

The meniscus • Measure to the bottom of the meniscus Chemistry

Using droppers • Like wash bottles, make sure the dropper tip doesn’t touch anything. • After you stop squeezing, the dropper sucks in air. • If there is a chemical on the tip of the dropper, it will suck that in too. Chemistry

Cleaning labware • Squeeze in some soap (only if really dirty) • Use a test tube brush if needed • Ask for another brush if needed • Rinse at least three times with tap water (or until all soap is gone) • Rinse once with distilled water • Put on drying rack or in other designated location. Chemistry

Laboratory Procedures