Density of Liquids

Lab: Density of Liquids

Pre-Lab Questions

1.  List the densities of some solids you have measured so far. (Ex. pennies, marbles, metal samples)

2.  How do you think the density of a liquid will compare with the density of a solid?

3.  Predict the three liquids, water, saltwater, and isopropyl alcohol, we will be measuring and calculating the density of today. List them most to least dense.

Materials

Balance

Graduated Cylinders (10 and 100 mL)

Dropper

Water

Saltwater

Isopropyl Alcohol

Procedures

Water:

1.  Find the mass of your 100 mL graduated cylinder.

2.  Using a dropper, carefully fill the graduated cylinder to the 10mL mark. Mass the graduated cylinder and liquid. Subtract the mass of the empty graduated cylinder and record the mass of the liquid in the data table.

3.  Add 10 more mL of water to the graduated cylinder to make a total of 20 mL. Mass the graduated cylinder and liquid. Subtract the mass of the empty graduated cylinder and record the mass of the liquid in the data table.

4.  Repeat step 3 for 30, 40, and 50 mL of liquid.

5.  Calculate the densities of liquid for each volume. Take an average of all volumes and record this value in the data table.

Isopropyl Alcohol

1.  Find the mass of your 10 mL graduated cylinder.

2.  Using a dropper, carefully fill the graduated cylinder to the 1 mL mark. Mass the graduated cylinder and liquid. Subtract the mass of the empty graduated cylinder and record the mass of the liquid in the data table.

3.  Add 1 more mL of water to the graduated cylinder to make a total of 2 mL. Mass the graduated cylinder and liquid. Subtract the mass of the empty graduated cylinder and record the mass of the liquid in the data table.

4.  Repeat step 3 for 3, 4, 5, 6, 7, 8, and 9 mL of liquid.

5.  Calculate the densities of liquid for each volume. Take an average of all volumes and record this value in the data table.

Saltwater:

1.  Repeat the same process as water.

Post-Lab Analysis

1.  The density of water is 1.0 g/mL and the density of isopropyl alcohol is 0.79 g/mL. Calculate how close your data averages were to the actual values by using the following percent error formula.

2.  Were you correct in your predictions about the densities of the liquids?

3.  Which substances are generally more dense, solids, liquids, or gases?

4.  What does this tell you about particle arrangement of molecules in solids, liquids, and gases?