The invincible soap bubble!
The materials required for this science fair project:
- 5 empty plastic cups
- 100ml of liquid detergent
- 500ml of water
- A bubble blowing toy
- 10ml of corn syrup
- 10ml of glycerin (may be purchased at pharmacies, including big chains like Walmart or Target)
- 10mg of sugar
- 10ml of lemon juice
- 1 stopwatch
- A measuring beaker
- A weighing scale
- 1 black marker pen
1. For this science fair project, the independent variable is the additive added to the bubble solution – soap, corn syrup, glycerin, sugar and lemon. The dependent variable is the length of time the soap bubbles are able to last before bursting. This is measured with a stopwatch. The constants (control variables) are the room temperature and the mixing ratio of the bubble solution.
2. Using the black marker pen, the 5 plastic cups are labeled as “soap”, “corn syrup”, “glycerin”, “sugar” and “lemon”.
3. Each cup is filled with 100ml of water. Another 20ml of liquid detergent is added to each cup and mixed with the water. Then, depending on the marking on the cups, 10 ml of corn syrup, glycerin, sugar and lemon is added to each cup and mixed once more. The cup marked soap will be the control and it contains only a mixture of water and detergent.
4. The bubble blowing toy is dipped into one of the plastic cups and a bubble will be blown. The stopwatch is started and it is observed how long the bubble lasts before it bursts. The experiment is repeated 5 times and the longest time clocked, is recorded in the table given below.
5. Procedure 4 is repeated using the solutions in the other 4 cups. The longest time taken before the bubble bursts is clocked and the results recorded in the table below.