Your Child Can Build a Lava Lamp

Your Child Can Build a Lava Lamp

Your child can easily build a lava lamp with a fun, science experiment using simple household items such as food coloring, Alka-Seltzer, vegetable oil and a bottle.  Funky balls of color moving around like a real lava lamp are created by chemical reactions.

What your child will need:

• Clear plastic bottle
• Vegetable oil
• Water
• Alka-Seltzer or tablets that fizz

Instructions:

• Fill the plastic bottle about one quarter full with water.
• Pour vegetable oil into the water in the bottle until it is almost full.
• Wait a short time until the water and oil have separated.
• Add about a dozen drops of any color food coloring to the bottle.
• Observe the food coloring falling through the oil and mixing with the water.
• Cut a tablet of Alka-Seltzer into five or six smaller pieces and drop one piece into the bottle. Watch the action start up as it appears to be a real lava lamp!If and when the bubbling stops, add another Alka-Seltzer piece.

What happened?

Guess water and oil do not mix very well!  The oil and water the child added to the bottle separated from one another, and the oil rose to the top because of its lower density than water.  Falling through the oil, the food coloring you added mixes with the water at the bottom.  The piece of Alka-Seltzer your child added releases small carbon dioxide bubbles of gas.  These rise to the top and bring some colored water with them.  When the gas reaches the top, it escapes and the colored water falls down.  The citric acid and sodium bicarbonate in the Alka-Seltzer causes it to fizz.  The reaction of the two with water form sodium nitrate and carbon dioxide gas bubbles that carry the colored water to the top.  Your child has created a lava lamp!