Stacking Fluids in a Bottle

In this instructable, you'll observe the density properties of different fluids.  This is particularly applicable to studying chemistry and engineering because the densities of fluids have much to do with characteristic reactions in flow through pipes and many other applications.

Obtain the required materials.
The things you will need are:

tape measure/ruler
1/8 cup of :  water
                    vegetable oil
                    liquid dish soap (green in color is best)
                    rubbing alcohol
                    honey
food coloring (not the same color as the soap; red or blue is best)
measuring glass
black expo marker or sharpie
16.9 FL oz bottle

Use the black marker to mark the 16.9 FL oz bottle into 5 equal sections. Here is where you can use the tape measure or ruler to mark the bottle every 1.5 inches (approximately).  Starting with the bottom section, label the sections in the following order: honey, dish soap, water, vegetable oil, and rubbing alcohol.  This is also the order in which the liquids should be poured into the bottle.

Pour the honey into the bottle and fill to the first line.

Slowly pour the dish soap into the bottle and fill to the second line.

Using the measuring cup, mix 1/8 cup water with approximately 6 drops of food coloring.  I would suggest using a dark color such as red or blue so that the different sections can be more distinguished from each other.

Tilt the bottle about 45 degrees from vertical and pour in the colored water.  Fill to third line.    (Note: The two first liquids are relatively dense.  Therefore, pouring them into an upright bottle is best so that they do not adhere to the side of the bottle.  The water and  the remaining liquids are less dense and mix together much more easily.  Therefore, it is necessary to try to slow their entry into the bottle as much as possible. It also helps to pour slowly.)

Tilting the bottle again, pour in the vegetable oil. Fill to the fourth line.
(NOTE: If the vegetable oil goes in too fast, the oil will mix with the water, and it'll be hard to tell them apart.)

Tilt the bottle one last time and fill the last section with rubbing alcohol.

You're finished!!
(Note:  If there are bubbles in the top section, don't worry.  Within an hour, all the bubbles should disappear.)