Liquid Layers

Concept: Density
Density is a measure of how much mass is contained in a given unit of volume. The formula for calculating the density of a substance equals its mass divided by its volume (Density = Mass ÷ Volume). Density is usually given in grams per milliliter (g/mL).

Read Aloud: Science Rocks! by Ian Graham

Ingredients:

      ·         ¼ cup Honey

      ·         ¼ cup Karo Syrup

      ·         ¼ cup Dish Soap

      ·         ¼ cup Water

      ·         ¼ cup Vegetable Oil

      ·         ¼ cup Rubbing Alcohol

      ·         Plastic Bottle
      ·         Food Coloring

 Demonstration:

      ·         Add food coloring to the clear liquids to make them more visible.

      ·         Slowly pour ¼ cup of each liquid into the plastic bottle, one at a time. Make sure that the liquids do not touch the sides of the plastic bottle as they are being poured. Let each layer settle before adding the next one.

      ·         As you pour, the liquids will layer on top of one another.

Experiment:

·         Can you predict the sequence of the layers if you know the density of each liquid?

·         Why do the layers of vegetable oil and rubbing alcohol switch places after a couple of days?

Observations:

The same amount of different liquids will have different weights because they have different masses. The liquids that have a higher density and weigh more will sink below the liquids that have a lower density and weigh less. The layers will always even themselves out because of their varying densities.