Chapter 1, Problem 5CHQ

Materials Needed:

• 1/4 cup dark corn syrup
• 1/4 cup dishwashing liquid
• 1/4 cup water
• 1/4 cup vegetable oil
• 1/4 cup rubbing alcohol
• A tall 12-ounce glass or clear plastic cup
• Food coloring
• Measuring cup
When you drop an ice cube into your glass of water, what happens? Everyone knows that ice floats… but, why? The simple answer is density.

Water and ice, even though they are made of the same substance, have different densities. Density is a measurement of the ratio of the mass of something to its volume. Remember the density equation (Density = Mass/volume).

For this experiment you will need to locate different liquids that can be found in kitchen and bathroom cabinets. One way you could determine which liquids have higher or lower densities would be to weigh them, but this experiment involves layering the liquids to learn something about the densities of these common household items.
Before you start your experiment, prepare 1/4 cup of rubbing alcohol with a few drops of food coloring (either blue or green) and prepare 1 /4 cup of water with food coloring (red or orange).

Take the 12-ounce clear glass (slim ones work best). Being careful not to get syrup on the side of the glass, pour the syrup into the center of the bottom of the glass. Pour enough syrup to fill the glass one-sixth of the way.
After you have added the syrup, tip the glass slightly and pour an equal amount of the dishwashing liquid slowly down the side of the glass. Be careful to add the next liquids slowly. Tip the glass slightly, and pouring slowly down the side of the glass, add first the colored water, then the vegetable oil, and finally the colored rubbing alcohol. 5. Why is it useful to know a substance's density?