Tag: science

Fireworks in a Jar

Materials:

  • Mason jar
  • Small bowl
  • 3-4 tablespoons of oil
  • Liquid food coloring
  • Fork

Instructions:

  1. Add oil to a small bowl. Add several drops of food coloring.
  2. Use a fork to gently mix the oil and food coloring.
  3. Fill your mason jar about 3/4 of the way with warm water.
  4. Slowly pour the oil and food coloring mixture into the mason jar.

The science behind it:

OIl is less dense than water so the oil will float at the top. Food coloring dissolves in water but not in oil. The colored droplets of food coloring will begin to sink because they are heavier than the oil.  Once they sink into the water, they will begin dissolving into the water making a tiny explosion like fireworks.

Dancing Corn Kernels

Materials:

  • Mason jar
  • Popcorn kernels
  • Water
  • Baking soda
  • Vinegar
  • Spoon
  • Tablespoon
  • Pan (to contain the mess)
  • Food coloring (optional)

Directions:

  1. Put the mason jar inside the pan so any overflow from the jar is contained.
  2. Fill the mason jar about 2/3 full with water.
  3. Add 2 tablespoons of baking soda to the water and stir until the baking soda is dissolved.
  4. Add a handful of popcorn kernels to the mason jar.
  5. Slowly pour about 4 tablespoons of vinegar to the mason jar.  If you add the vinegar too quickly, the combination may just overflow into the pan.  After a little while, the popcorn kernels will start dancing in the jar.  If this doesn’t happen, give the liquid a quick stir.

What’s happening?

The secret to the dancing corn is the reaction between the vinegar and baking soda.  When baking soda (a base) is mixed with the vinegar (an acid), they produce carbon dioxide (a gas)!  The carbon dioxide bubbles lift the corn, but as the bubbles pop, the corn falls back down!

 

Walking Rainbow

The walking rainbow is a fun experiment for kids to set up and observe. Kids will be able to see the experiment starting almost immediately and then check back every 30 minutes or so to see things moving along.  The walking rainbow experiment demonstrates a few basic scientific concepts – capillary action and color mixing.

Materials:

  • Clear glasses – You will need an odd number of cups.
  • Water
  • Food coloring
  • Paper towels

Instructions:

  1. Line the cups up on a table.  Fill every other cup with water.  Leave about 1 inch at the top.
  2. Add food coloring to the cups with water. Add a different color to each cup.
  3. Fold a piece of paper towel into thirds.  You will need a piece of paper towel for each cup of water you have.
  4. Put one end of the folded paper towel in the colored water and the other end in the empty cup.

What’s happening?
The walking rainbow experiment demonstrates a few basic scientific concepts – capillary action and color mixing.

When the paper towels are rolled up and placed between two jars, they will demonstrate capillary action. Capillary action is how liquid can move up something, rather than follow the usual pull of gravity and pull down. This causes the water to move up the paper towel and into the next jar. Capillary action is how plants pull water from the soil and up into their leaves to keep watered.

Once the paper towels pull color from the base red, blue, and yellow primary color jars, the resulting mixture creates the secondary colors of green, purple, and orange, completing the rainbow.