CHEM 101L FINAL QUESTIONS AND ANSWERS
The volume marking at the sealed bottom of a buret segment is 48.60 mL, and has
markings for every 0.1 mL. When water is added, the bottom of the meniscus sits
about halfway between the line for 28.3 mL. What volume of water is contained in
the buret segment?
20.35 mL
When calculating the displacement volume of the thermometer, the volume
reading on the buret is 28.47 mL without the thermometer and 27.87 mL with the
thermometer in place. How many significant figures should be recorded for the
displacement volume of the thermometer?
2
While weighing out a reagent for use in an experiment, a student finds the 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
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 reading the label on a reagent container, what are the three most important
pieces of information?
Hazard warnings, Name, Concentration
Why should you inspect glassware for chips, cracks or chemical residues before
using it?
Weak spots = can burst
If the glassware breaks during use, experimental results may be lost
Chemical residues from previous experiments can cause unwanted and potentially
dangerous side reactions
In some circumstances, using the fire extinguisher may be necessary. Which of
the following scenarios represents an appropriate use of a fire extinguisher?
A handful of paper towels in the garbage has caught fire, the fire is small and relatively
contained within the trash can.
What is the best resource for understanding the nature of the chemical hazards of
materials you work with in lab?
Safety Data Sheets
If you need to work with a flammable or volatile solvent, which piece of lab
equipment should you be sure not to use?
Bunsen or Meker burner, or anything with an open flame
When should you be sure never to use a sealed container and/or secondary
containment in the laboratory?
When heating a solution over a hot plate, burner, or heating mantle
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 volume marking at the sealed bottom of a buret segment is 48.60 mL, and has
markings for every 0.1 mL. When water is added, the bottom of the meniscus sits
about halfway between the line for 28.3 mL. What volume of water is contained in
the buret segment?
20.35 mL
When calculating the displacement volume of the thermometer, the volume
reading on the buret is 28.47 mL without the thermometer and 27.87 mL with the
thermometer in place. How many significant figures should be recorded for the
displacement volume of the thermometer?
2
While weighing out a reagent for use in an experiment, a student finds the 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
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 reading the label on a reagent container, what are the three most important
pieces of information?
Hazard warnings, Name, Concentration
Why should you inspect glassware for chips, cracks or chemical residues before
using it?
Weak spots = can burst
If the glassware breaks during use, experimental results may be lost
Chemical residues from previous experiments can cause unwanted and potentially
dangerous side reactions
In some circumstances, using the fire extinguisher may be necessary. Which of
the following scenarios represents an appropriate use of a fire extinguisher?
A handful of paper towels in the garbage has caught fire, the fire is small and relatively
contained within the trash can.
What is the best resource for understanding the nature of the chemical hazards of
materials you work with in lab?
Safety Data Sheets
If you need to work with a flammable or volatile solvent, which piece of lab
equipment should you be sure not to use?
Bunsen or Meker burner, or anything with an open flame
When should you be sure never to use a sealed container and/or secondary
containment in the laboratory?
When heating a solution over a hot plate, burner, or heating mantle
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
