Hobbies And Interests
Density and Buoyancy - Dancing Raisins Experiment
In order to illustrate density, the use of matter in all of its forms (gas, liquid and solid) is used in this experiment. For this experiment, you will need a large, clear glass, fresh club soda and raisins. Pour the club soda into the large glass, while adding a few raisins at the same time. At first, the raisins will sink to the bottom of the large glass. However, once the carbon dioxide bubbles attach themselves to the raisins' surfaces, they will float to the surface. When the raisins reach the surface, the carbon dioxide bubbles that attached themselves to the raisins will release their gas into the air, forcing the raisins to once again sink. This will continue to happen, which creates the "dancing raisins" effect.
Fizzing and Foaming Experiment
This foaming and fizzing experiment is meant to explain visually how batter rises during the cooking process. You will need baking soda (1 tbsp.), laundry detergent (1 tbsp.), water (3/4 cup), vinegar (1/4 cup), food coloring (several drops), drinking glass (12 oz.) and a plastic tray or cookie sheet. First, put the glass on the cookie sheet or plastic tray so that it can catch anything that comes out of the glass and avoid a mess. Pour the laundry detergent and baking soda in the glass first, followed by the water and food coloring. Once this is complete, stir everything and add the vinegar quickly. You will immediately notice the foaming and fizzing, which will fill the cup and then spill over top of it. Have the kids look at the tiny bubbles on the tray or sheet -- these foamy bubbles are carbon dioxide.
Greenhouse Effect
This experiment is meant to demonstrate to kids how the Greenhouse Effect works. The Greenhouse Effect is essentially the process by which thermal radiation from earth is absorbed by atmospheric greenhouse gases and then re-radiated in a number of directions. You will need two Ziploc bags (1-gallon size), three thermometers, two plastic cups filled a little more than halfway with and two Alka-Seltzer tablets. Mark one of the Ziploc bags "Experimental" and mark the other bag "Control." In each of the Ziploc bags, place a cup without spilling any of the water. Afterward, put one of the thermometers in each bag next to the cups; the third thermometer will not be placed in any bag. Take both bags and the thermometer outside and place them all either on the concrete or the grass (make sure the bags haven't been sealed). Place the Alka-Seltzer tablets in the "Experimental" bag and seal it quickly. Seal the "Control" bag as well. Leave the two bags and the thermometer outside for two hours. Check on all the materials at the end of the two hours and kids will notice that the "Experimental" bag temperature is higher than the thermometer alone and the "Control" bag.
Soapy Bubbles with Dry Ice Experiment
This experiment shows kids how carbon dioxide (in dry ice form) reacts with chemicals that are already "bubbly" in nature. It is important to conduct this experiment in as safe a manner as possible. Dry ice is dangerous when coming into contact with skin, so the use of tongs or gloves is absolutely necessary. You will need dry ice, a tall glass, warm water, plastic tray, liquid dish soap and gloves or tongs. Place the glass on the tray. First, fill the glass up with the warm water before adding a tiny bit of the dish soap. Next, carefully add a piece of dry ice to the mixture. The carbon dioxide is trapped by the soap in the water which then creates bubbles. Those bubbles do not remain in the glass; rather they will overflow causing tiny bursts or explosions as they drop onto the tray. This demonstrates how carbon dioxide is trapped and then released.