This experiment was constructed to aid in the practice of using the volumetric system and the glassware that determines volume. Volumetric glassware contains an accurate amount of liquid and also measures the volume accurately.
Density is a measure of how much matter takes up a certain amount of space or volume. The more matter you can pack into a certain space, the denser it is. Although we often confused the two, density and weight are actually two different measurements. Weight is defined as the mass of an object times the force of gravity. In our world where we have gravity forcing things downward, a denser object will be heavier too.
One way to check the concentration of a liquid is by measuring density and using volumetric glassware to do so. For many years, soap was made with animal fat and a lye solution. To determine if the concentration was just right, a raw egg was placed into the solution and if it “just floated” the concentration was correct.
Chemical and Reagent
An aqueous sodium chloride solution was prepared by adding solid sodium chloride to 1500 mL of distilled water while stirring until an uncooked egg floated. The amount of salt added had an unknown mass; however the density was determined indirectly by the use of four different techniques: burette, Mohr pipette, volumetric pipette, and a volumetric flask.
For each technique, a system was put in place to determine how much a volume of solution weighed. An empty flask was used to contain a delivered amount of solution. The mass of the flask was taken before the addition of the solution and then again after the addition. By difference, it was determined how much the solution weighed for a certain volume. This technique was used for the burette, Mohr pipette, and for the volumetric pipette. The volumes for each technique varied. The volumes of the salt solution that were delivered...