Lava Lamp

Steps:

• Fill the empty plastic water bottle to 1/4 the height of the bottle

• Fill the rest of the bottle with your vegetable oil

• Wait one minute for the oil and water to separate

• Once the oil and water are separated, choose one or two food dyes to add to the bottle (Lighter colors make cooler lamps)

• Add 5-10 drops of food coloring

• Break up one Alka-Seltzer tablet into small pieces and add one piece at a time

• Observe the reaction as it happens

• Once the mixture has stopped bubbling, replace the cap on the bottle and twist or shake the bottle in different directions to observe the reaction.

[CAUTION]

• Do not eat or drink any of the lab materials used in the experiment

• Keep your eyes and face away from the bottle after the ingredients have been added

• Wash your hands thoroughly when the experiment is done

Scientific Explanation!

In the experiment, the vegetable oil is less dense than the water so the it floats on top of the water. The food coloring has the same density as the water so it sinks to the bottom of the bottle. Density is the compactness of something. When we added the Alka-Seltzer tablet, it dissolved and made the water and oil separate more. When it dissolves, the tablet turns to gas and rises to the top since it is less dense than water; this gas is what the bubbles in our lamp are! The reaction will repeat as you keep inserting tablets but ends as the Alka-Seltzer completely dissolves. Have fun and watch your lava lamp erupt!

Bonus Fact Explanation!

When you cap the water bottle, you are keeping that gas, also known as the bubbles in the bottle. The constant increase of this gas creates lots of pressure since the particles want to escape into a less packed area. So they build up and begin to condense at the top of the bottle! When a gas condenses it turns to water. So, when you open the bottle, you'll hear a fizzy air noise; this noise is the sound of the gas particles' (bubbles') high pressure releasing into a much more open space. The longer you cap he bottle, the louder and fizzier the noise will be!

Works Cited:

Lava Lamp. (n.d.). Retrieved April 05, 2021, from https://www.sciencefun.org/kidszone/experiments/lava-lamp/