Lab 3C - Graphing Quiz

What are the proper disposal methods for the reagents used in the lab (select all that apply)

• Pour ethanol down the drain with plenty of water

• Pour sodium chloride solution down the drain with plenty of water

• Pour ethanol into designated waste container

• Pour salt water into designated waste container

With regards to Erlenmeyer flask, your group will

• Use the same flask throughout the experiment

• Use a different flask for each liquid

• Take turns sharing three flasks with the class for each liquid

• Share the same flask with the class for the entire experiment

What is the first thing thing to do on the day of the lab

• Complete the pre-lab questions

• Create a flow chart

• Determine the mass of a clean, dry 250 mL Erlenmeyer flask

• Put on a lab apron and safety goggles

After determining the mass of the empty Erlenmeyer flask, you will need to

• Determine the mass of the liquid plus the flask using the centigram balance.

• Dispense your assigned volume of one of the liquids from a burette to the flask and record results later

• Record the initial volume in the burette and dispense 20 mL of one of the liquids from the burette to the flask. Record the final volume in the burette and total volume dispensed

• Record the initial volume of one of the liquids in the burette and dispense your assigned volume into the flask. Record the final volume in the burette and total volume dispensed

Each time you measure a different liquid (select all that apply)

• Empty the flask before each liquid

• Do not empty the flask

• Determine the mass of each volume by subtracting the previous balance reading

• Clean and dry the flask before each liquid

250 mL Erlenmeyer flasks

• Have a standard and identical mass

• Can have different masses

• Have different masses but the difference is too small to measure with a centigram balance

• None of the above

When dispensing volume from the burettes

• It is very important to precisely obtain your assigned volume

• The precision of the measurement is not as important as the accuracy

• Obtain your assigned volume as accurately as possible, but recording the actual volume dispensed is most important

• The volumes dispensed should be identical between the different liquids

The class data

• Does not need to be recorded

• Will be available on google classroom and does not need to be included in the lab report

• Will be recorded in a table in your lab report

• None of the above

The centigram balance will allow you to record significant figures to the nearest

• 1 g

• 10^-2 g

• 10^-3 g

• 0.1 g

The last thing you should do before leaving the laboratory is

• Pour any leftover reagents into the appropriate container

• Wash your hands thoroughly with soap and water and clean under your fingernails

• Record the class data into your table

• Determine the mathematical relationship between the experimental variables