A Better, Safer, Lava Lamp
I. Introduction
While babysitting, I found that the kids I was taking care of loved lava lamps more than anything and absolutely enjoyed science experiments. I decided to make a lava lamp with them using materials found at home; food coloring, vinegar, vegetable oil, and baking soda. However, since there were no guidelines as to when to add ingredients or how much of an ingredient to add, I had to conduct several trials based on my schema to create the perfect lava lamp. I knew that baking soda would be the final ingredient because it is always quick to react. I also knew from previous experiments that Alka Seltzer could be an alternative to baking soda. Since the expected outcome of this experiment was circulation of colored bubbles in the graduated cylinder, I knew that part of this investigation would be to find out which of the following two was denser: vinegar or vegetable oil.
II. Hypothesis
If we pour 50 mL of colored vinegar, 25 mL of vegetable oil, and finally five small scoops of baking soda into a graduated cylinder in this order, then we will have successfully created a lava lamp.
III. Materials

40-50 mL vegetable oil
50-60 mL vinegar
Small Dixie cup of baking soda
Popsicle stick (scoop)
Food coloring
Graduated cylinder

IV. Procedures
Trial One
Pour 50 mL of vinegar into the graduated cylinder
Color the vinegar with a few drops of food coloring
Add 25 mL of vegetable oil
Then proceed to add 4 scoops of baking soda
After completing these steps we found that our order of ingredients was correct but the amount of the ingredients could be perfected. There was a lot of vinegar and only a small amount of vegetable oil. There were not enough bubbles circulating as well which meant that more baking soda was needed. We decided to slightly even out the amount of vegetable oil and vinegar we used in order to make the lava lamp more appealing.
Trial Two
Pour 50 mL of vinegar into the graduated cylinder
Color the vinegar with a few drops of food coloring
Proceed to add 35 mL of vegetable oil
Add 5 scoops of baking soda
Trial Two was far more successful and produced a more effective and appealing lava lamp. The vinegar and vegetable oil evened out nicely and there were enough bubbles circulating in the graduated cylinder.
The control group for this experiment would be vinegar, vegetable oil, and food coloring. The independent variable was the different orders of the ingredients. The dependent variable was the amount of ingredients added. We evaluated our success based on how similar our homemade lava lamp was compared to an actual lava lamp. There were only two trials in this experiment due to a time crunch but the initial result, a successful lava lamp, was achieved.
V. Data Collection/Analysis

Trial One
Vinegar (mL)
Food Coloring
Vegetable Oil (mL)
Baking