Chem 102L Final

My most important role in lab is: A. Working safely. B. Learning all the techniques. C. Writing excellent lab reports. D. Arriving to lab on time

A. working safely

When working in the lab, you should always remove your gloves when: I. Typing on your laptop keyboard II. Leaving the laboratory III. Picking up your pen to record observations in the lab notebook IV. Using the doorknob V. Using the laboratory phone

All of these are cases when you should first remove your gloves.

If you choose to wear loose clothing, large or dangling jewelry, or contact lenses to lab, which of the following statements best represents how you should proceed? Make sure all loose clothing or jewelry can be confined by the lab coat. Make sure to wear your goggles securely over your contact lenses and check with your lab manual and TA to be sure you will not be working with any volatile or fume-producing reagents Make sure none of the jewelry will catch on your clothing or accidentally cut your gloves, and don't wear anything too valuable. All of these statements are reasonable compromises if you MUST wear these items to lab, but the best and safest practice is to leave them at home and dress for lab intentionally.

All of these statements are reasonable compromises if you MUST wear these items to lab, but the best and safest practice is to leave them at home and dress for lab intentionally.

When the procedure calls for making a more dilute solution of an acid, or mixing an acid with other solutions, what is the correct order of steps?

Always Add Acid - Either add all of the water or non-acid component first, or add a significant portion, before adding the acid to the mixture. This helps to minimize the heat generated, which could otherwise create dangerous fumes or reactions.

Which of the following is the reason backpacks must be stored during lab? Backpacks on the floor of the lab or on the benches may be exposed to hazardous materials, which might then lead to student exposure outside the lab. Backpacks on the floor present a tripping hazard to students in lab, which may lead to spills and other incidents. Both of these are good reasons to keep nonessential items stored properly.

Both of these are good reasons to keep nonessential items stored properly.

The proper process(es) for disposing of liquid waste containing hazardous material could be

Bring the waste to the liquid waste bottle in the fume hood. Check the liquid levle in the wast bottle. If the level is within 2" of the neck bottle, notify your TA so that the bottle wont be overfilled. Bring the liquid waste bottle and funnel to your bench. Check the liquid level is the waste bottle. As long as the liquid is not yet into the funnel, proceed.

Which of the following statements is FALSE when it comes to working with hot glassware. A. Hot objects do not always appear hot. B. When handling hot glassware, be sure to use the silicone or rubber "hot hand" provided to prevent burns. C. If you receive a small burn on your hand, you should immediately notify your TA and run cold water of the burn. C. To check if a piece of equipment is hot, quickly touch it, but do not hold your finger in place to prevent burns. E. NEVER TOUCH HOT GLASSWARE!

C. To check if a piece of equipment is hot, quickly touch it, but do not hold your finger in place to prevent burns.

When reading the label on a reagent container, what are the three most important pieces of information? Chemical formula Concentration CAS Number Hazard warning(s) Color Name

Chemical formula Hazard warning(s) Name

When dealing with hazardous materials generated in the lab, select all the guidelines that are applicable

Collect ALL hazardous material for proper disposal. Organize the experiment to generate the least amount of hazardous material possible. When in doubt, dispose of materials as though they are the most hazardous type to be safe.

What should you do if you get chemicals on your gloves or they appear stained?

Dispose of othe dirty gloves and replace them with new ones, rinsing your hand and telling your TA if you think something particularly hazardous has permeated them or if you feel any irritation

When should you be sure to wear full PPE (proper attire, lab coat, goggles) in the laboratory? (Check all that apply.)

During a lab quiz. While cleaning up after experimental work is done. While waiting in the lab room for a friend to finish. As soon as you enter the lab, and until you are ready to walk out the door. Once the experimental work has begun.

If you need to leave the lab to go to the restroom you should A. Remove your gloves and recycle B. Remove your lab coat and hang it on the coat rack by the door. C. Ask a lab partner to watch your equipment. D. Notify your TA of your plans to momentarily leave the room . E. All of the Above F. Only A and B

E. All of the above

Mesh Shoes (contains holes) is appropriate for lab (T or F)

False

Open Shoes are appropriate for lab (T or F)

False

Slides are appropriate for lab (T or F)

False

Tank tops are appropriate for lab (T or F)

False

If you need to work with a flammable or volatile solvent, which piece of lab equipment should you be sure to use? Bunsen or Meker burner, or anything with an open flame. Hot plate. Heating mantle. Fume hood with good ventilation. Volumetric flask.

Fume hood with good ventilation.

When should you inspect the glassware in your lab drawer for chips, cracks, or chemical residues?

Glassware should be inspected at all of these times to prevent accidents, injuries, or unwanted complications during experimental work.

When should you immediately turn off the gas valve for a Bunsen or Meker burner? Check all that apply.

If you must leave the open flame unattended and there is no one else to monitor it. If you smell gas in the room. If the flame suddenly goes out.

Your lab partner accidentally gets a mist of your solution in her eye. You immediately help her to the eye wash to rinse it. After about a minute, she feels better and is ready to get back to work. You should still do the following before the TA fills out the incident report:

Keep her in the eye wash for at least 15 minutes, and then make sure she goes to student health, just to be sure.

Your lab partner accidentally spills some acid on his wrist and watchband. You should: Select all that apply.

Let the TA inspect his wrist to see if it is okay. Remove the watch and watchband immediately, and rinse his wrist for at least 15 minutes to be sure all hazardous material has been washed away. Rinse the watch band before allowing him to put it back on.

While weighing out a reagent for use in an experiment, a student finds he has leftover reagent. The student should:

Place the excess reagent in the appropriate solid or liquid waste container to prevent contamination of the stock reagent..

Which of the following must be completed before the pre-lab lecture in lab? Select all that apply.

Put on your lab coat. Store your backpack, cell phone, jacket, and all other nonessential items in designated storage areas. Tie back long hair. Put on your goggles.

If any chemical makes contace with your hand you should

Remove your glov,e put your hand under running cold water for 15 minutes, Contact your TA, fill out an incident report

What is your BEST resource for understanding the nature of the chemical hazards of materials you work with in lab?

Safety Data Sheets (SDS) that should be consulted before coming to lab each week.

Which of the following precautions is important when using a Bunsen burner or Meker burner? Select all that apply.

Set up your work space so that wires and cables cannot accidentally make contact with the flame or hot glassware and melt. Always tie back hair, even long bangs, that might accidentally come in contact with the flame. Set up the work space so that flammable materials - notebooks, paper towels, other reagents, etc. - are far away from the burner to prevent them coming in contact with the hot surface. Set up your work space with the burner in a secure location away from the edge of the bench so that you won't accidentally bump it and spill hot liquids. Remember that any glassware heated by the burner will look the same when hot as cold, and will not cool down until well after the burner has been shut off.

Your lab partner accidentally trips and douses the front of your lab coat and shirt with a hazardous material. The TA immeidately takes you to the safety shower, since the spill has soaked into your clothing. What do you need to do at this point?

Stay under the shower for at least 15 minutes. Remove your shirt and any other clothing that were in contact with the chemical.

Which of the following is a NOT behavior that can pose a safety risk in the laboratory environment?

Staying focused on your own experiment and not being distracted by what nearby groups are doing.

Suppose a beaker of solid reagent drops onto the bench and cracks. Which of the following represents the correct disposal:

To the extent possible, solid reagent should be added to the solid waste container and broken glass should be added to the glass waste. Hazardous materials should never be added to the glass waste, and broken glass should only be allowed in the solid waste with the TA's approval.

Double gloving can provide additional protection against hazardous chemicals. (T or F)

True

Everyone should be wearing PPE in the lab. (T or F)

True

If ankle is exposed, socks should be worn to cover the bare skin. (T or F)

True

It is important to know the location of the safety equipment (T or F)

True

Joggers are appropriate for lab (T or F)

True

T shirts are appropriate for lab (T or F)

True

In some circumstances, materials that are being heated in the lab could catch fire. If a flammable substance in a beaker should catch fire while you are working but the flames are relatively contained, what is a simple method for extinguishing the flame?

Turn off the heat source immediately, and use a watch glass to cover the beaker and minimize the oxygen around the flame.

What is the most important consideration to preserve safety when it is necessary to feed glass tubing, thermometers, or other apparatus through a rubber stopper?

Using the correct hand position so that if something goes wrong you can avoid coming into contact with broken or sharp ends.

When should you NEVER use a sealed container ?

When heating a solution over a hot plate, burner, or heating mantle.

For which of the following situations should you be sure to notify your TA? Check all that apply.

You begin to feel faint and dizzy in lab because you had to skip lunch. You accidentally pick up a beaker from the hot plate, not realizing that it was already hot, and the edge of the beaker leaves a small red mark on your thumb. You arrive in lab, but realize that your cold medicine is making you feel groggy.

After disposing of a material into a hazardous waste container, always

close the lid

Accuracy

how close the measurement is to the true value.

Precision

how close the measurements are to each other; the measured value can be redone and get similar measurements

Random Uncertainty

rises from uncontrolled and/or uncontrollable variables. This can affect the results in both ways, while systematic can usually only affect the results in one direction. Influences precision

Systematic Uncertainty

uncertainty that arises from something in the equipment or a flaw in the experiment and is reproducible. Affect Accuracy