#367. Density of Liquids

Science, level: Middle
Posted Fri Mar 27 17:38:25 PST 1998 by Travis Huber (Thuber@mason.k12.ky.us).
Mason County MIddle school, Maysville, KY
Materials Required: graduate cylinder, triple beam, various liquids
Activity Time: 2 50 minute lessons
Concepts Taught: Density, intrinisic property, graphing

Density of Liquids

Question: Is density an intrinsic or extrinsic property of matter?

In this lab exercise you will determine the density of various amounts of different liquids in order to determine if density in an intrinsic property (depends on the type of matter) or if density is an extrinsic property (dependent on the amount of matter). Density is the ratio of mass of an object to its volume and is generally reported in grams per cubic cm (g/cm3). You need to remember that a ml is the same as a cubic centimeter.

· write your hypothesis now on your own sheet of paper
· read the procedure below and construct a data table for the experiment - follow the example provided

Procedure
1. Determine the mass of a clean dry graduated cylinder - record in data table.
2. Measure out a given volume of one of the liquids (A, B, C) - record in data table.
3. Determine the mass of the graduated cylinder and the liquid together - record.
4. Subtract the mass of the cylinder from the mass found in step 3 - this gives you the mass of the liquid alone - record
5. Calculate the density of the liquid by dividing the mass by the volume -record
6. Repeat steps 1-5 for 2 different amounts of the same liquid.
7. Repeat steps 1-6 for the other 2 liquids provided.

Sample Table
Measurement A1 A2 A3 B1 B2 B3 C1 C2 C3
Mass of graduated cylinder

· Show all calculations like the example shown on the black board.
· Graph the Data you collected - construct a bar graph of density (y-axis) versus type of liquid (x-axis) and construct a line graph (all 3 liquids on the same graph) of volume (x-axis) versus mass (y-axis).
· Write a conclusion that includes the following items:
1. Compare the 3 densities you calculated for each liquid (A1, A2, A3), and compare the average density of the 3 different liquids (A, B, C).
2. Discuss the 2 graphs - what does each show about density, what does the line graph show about the 3 liquids, does the line graph show anything that helps support or contradict your hypothesis?
3. How does the data support or contradict your hypothesis?
4. Make a final statement of whether density is intrinsic or extrinsic.
5. Discuss how this data could be used to determine the identity of these liquids if the labels fell off their bottles.