CHM 113 Investigation 2-.docx - Investigation 2: Lets Get...

Investigation 2: Lets Get Familiar: Becoming Accustomed to
Lab Equipment and Procedures
Thursday 8:30 -10:20 AM
CHM 113
Introduction
Part 1 - Determining Precision and Accuracy of Common Glassware
In part one of this lab, the accuracy and precision of common glassware was measured.
Equipment such as beakers, burets, graduated pipettes, and graduated cylinders were tested.
Each of these glasswares is commonly used in the laboratory, mostly to hold and deliver certain
volumes of liquids, but each is unique in the accuracy in which they can measure these volumes.
This accuracy was tested, as in this part of the lab, measured volumes were compared with
“theoretical” volumes by using mass and density calculations. The purpose of this lab was to
familiarize the group with the lab equipment, and to allow the group to understand which
glassware should be used based on its accuracy. Of course all measurements and calculations

were made to the proper amount of significant figures so that the results could be the most
accurate based off of the known information.
Part 2- Determining volume and mass of a drop of water
In the second part of the lab, mass and density was used to find the volume of a drop of
water. The mass of 20 drops of water was found and was used with the known density of water to
calculate the volume of 20 drops of water. From here, the volume of one drop of water was easily
found. This process familiarized the group with more precise measurements, as well as how to
use the balance more effectively.
Part 3- Measuring solids with an electronic balance
Using an electronic balance correctly is another difficult task in order to perform the lab
successfully. In this part of the lab, the group learned how to use the an electronic balance and
then determined how much mass was lost when transferring the solids. In order to achieve the
best possible results for this lab, it is crucial to keep all records.
Part 4- Dilution of Stock Dye Solution
In the fourth part of the lab, the the equation M1V1=M2V2 used, and volumes of water
and stock dye were measured to make solutions with different concentrations. This equation
helped the group find the ratio of stock dye to distilled water, so that the solutions could be
made. Once the ratios were known, the solutions were mixed, and the observations were
recorded. This part of the lab helped the group practice how to measure volumes of liquids, as
well as familiarized the group with concentration and mixtures, and with visual observations.
Procedure
Part 1 - Determining Precision and Accuracy of Common Glassware

The materials used in this part of the lab were an electronic balance, plastic pipette,
water, 50 mL, beaker, 10 mL graduated cylinder, 10 mL graduated pipette, and 50 mL buret.