Experiments & Activites

Magic Milk

Create unique patterns of color with a few common ingredients.

Materials:

  • Shallow dish
  • Milk (2% , whole, or half and half work best)
  • Food coloring
  • Cotton swabs
  • Dish detergent

Steps:

  • Put some milk in the shallow dish, completely covering the bottom.
  • Add a few drops of food coloring to the middle of the dish of milk, being careful not to mix it with the milk.
  • Put a little dish soap on the end of a cotton swab.
  • Touch the non dish soap-covered end of the cotton swab to one of the spots of food coloring in the dish. What happens?
  • Now touch the dish soap – covered end of the cotton swab to one of the spots of food coloring in the dish. What happens?

How does it work?

The dish detergent contains phosphates and enzymes that react with the vitamins, minerals, and fats in the milk.  These reactions cause the food coloring to get pushed around the dish in the colorful patterns you see.  Since the soap is reacting with the fats in the milk, it is best not to use skim milk with this activity.

From www.chemistry.learnhub.com

Singing Balloons

Create a unique noise with just two materials!

Materials:

  • Latex balloon
  • Hex nut

Steps:

  • Carefully squeeze the hex nut through the mouth of the balloon, making sure that the nut goes all the way into the balloon.
  • Blow up the balloon and tie off the end.
  • Hold the balloon in your hand like a basketball or bowling ball, gripping at the tied off end.
  • Holding the balloon with your palm down, swirl the balloon in a circular motion.  What happens when the hex nut begins to roll inside the balloon?

How does it work?

The unique edges of the hex nut vibrate against the sides of the balloon, creating the singing noise.

From:  www.hookedonscience.org


pH Tester

Is it an acid or a base?  Use this smelly solution to find out!

Materials:

  • Red cabbage
  • Water
  • Blender
  • Strainer
  • Clear glasses or cups
  • Apron or other cover-up
  • Gloves
  • Chemicals to test, such as Vinegar, Baking Soda, Lemon juice, Washing soda, Laundry Detergent, pop, Alka-Seltzer

Adult supervision is recommended for this project

Steps:

  • Make red cabbage juice by blending one cabbage leaf with two cups of water until liquefied.  Use this ratio to make as much cabbage juice as you want.  It will be smelly!
  • Carefully strain the juice to remove the big chunks of cabbage
  • Add some of the cabbage juice to the glasses or cups.  Use a clean cup for each chemical you want to test.
  • Carefully add some of one of your test chemicals to one of the cups with the cabbage juice.  Does it change color?  The juice should turn red for chemicals that are acidic (pH below 7), and green for those that are basic (pH above 7).  The  juice will stay a purplish color if the chemical is neutral. (pH of 7)
  • Test the rest of your chemicals, using a separate cup for each one.

How does it work?

Red cabbage contains a natural pH indicator.  A pigment molecule called flavin will turn red in the presence of an acid, and green in the presence of a base.

From chemistry.about.com


Pop Rocks Experiement

Make this candy a fizzy eruption!

Materials:

  • Small cups (8oz or less)
  • Water
  • Pop Rocks
  • Lemon Juice (about 1/8 of a cup)
  • Baking Soda (less than a tablespoon)
  • Towels
  • Spoon

Steps:

  • Put some water into your cup.  Add the pop rocks.  They will start to pop.
  • Next add in the baking soda.  You may have to stir it a little to dissolve.
  • Finally add in the lemon juice.  The mixture should start to fizz and erupt from the cup!

How does it work?:

Pop rocks candy “pops”  because of the CO2 contained inside of them that is released when mixing the candy with water.

The baking soda (sodium bicarbonate) reacts with the contained CO2 as well to rapidly expand and rise.  The lemon juice, which contains citric acid, breaks down this process to cause the “fizz”.

From www.poprockscandy.com

 


Make your own Rock Candy

Grow sugar crystals that you can eat!

Materials:

  • 1 cup of water
  • 3 cups table sugar (sucrose)
  • Clean glass jar
  • Pencil or butter knife
  • String (cotton or wool, crystals won’t form on a nylon string)
  • Pan or bowl for boiling water and making solution
  • Spoon or stirring rod
  • Food coloring (optional)

Adult supervision is recommended for this activity

Steps

  • Tie the string to a pencil or butter knife.  Set the pencil or knife across the top of the jar and make sure that the string will hang into the jar without touching its sides.  It should also nearly touch the bottom.
  • Boil the water.  If using a microwave, remove the water carefully so you don’t get splashed!
  • Stir in the sugar a teaspoonful at a time.  Keep adding sugar until it will no longer dissolve and starts to accumulate at the bottom of the container.  This means your solution is saturated.  A saturated solution is important to make sure your crystals grow quickly.  However, if you use too much sugar, the crystals will grow on the undissolved sugar and not on your string.
  • Add food coloring if you would like colored crystals
  • Carefully pour your solution into the clear glass jar.  Try not to get any undissolved sugar in the jar.
  • Place the pencil over the jar and let the string dangle in the liquid.
  • Set the jar somewhere where it will be undisturbed.  You can cover the jar with a towel or a coffee filter to keep dust out.
  • Check on your crystals after a day.  You should be able to see the beginning of growth on the string.
  • Let the crystals grow until they reach the desired size or have stopped growing.  Pull out the string and allow the crystal to dry.  You can eat them or keep them. 

How does it work?

When you saturate the boiling water with sugar, you are creating a supersaturated solution.  As this solution cools, the excess crystals of sugar begin to come out of the solution and accumulate on your string.
 
From chemistry.about.com


Sink or Float?

Test the density of different objects

Materials:

  • Variety of objects to test
  • Clear bin filled with water

Steps:

  • Divide the objects into to two piles:  One pile for the objects you think will sink, one pile for the objects you think will float.
  • Test the objects by putting them into the bin of water.  Some objects may react differently depending on how you put them in the water 

How does it work?

Density is the main factor in wether an object will sink or float.  Density refers to how tightly packed together molecules are in an object.  It is measured as mass per unit of volume.  Those objects that are less dense than water will float, while  objects that are more dense than water will sink.  Having a lot of air in an object will lower its density, making it more likely to float.


Volcanoes

Materials:

  • Small paper drinking cups (at least 2)
  • Tape
  • Baking Soda
  • Vinegar
  • Dish Soap
  • Towels
  • Spoons
  • Baking sheet or other item that will catch the mess

Steps:

  • Add some baking soda to the bottom of one of the cups.  Place it on the baking sheet.
  • Add a squirt of dish soap and some food coloring to the baking soda.
  • Cut a hole in the bottom of the other paper cup.  Place this cup upside down on top of the cup with the baking soda.  Tape the cups together.
  • Pour the vinegar through the hole in the cup.
  • Watch your volcano erupt!

How does it work?

When the acidic vinegar and the basic baking soda are mixed together, they create carbon dioxide as one of their products.  The carbon dioxide and the soap create foamy bubbles that erupt out of the cup.

From www.yahoo.com


Bubbling Lava Lamp

Create a bubbling reaction that looks like a real lava lamp!

Materials:

  • Plastic Soda Bottles
  • Vegetable Oil
  • Food Coloring
  • Alka-Seltzer Tablets
  • Large Flashlights
  • Water

Steps:

  • Fill the bottle ¾ full with vegetable oil
  • Fill the rest of the bottle with water
  • Add ten drops of food coloring (the food coloring will only color the water, not the oil)
  • Divide the Alka-Seltzer into 4 pieces
  • Drop one of the tiny pieces of Alka-Seltzer into the bottle.
  • When the bubbling stops, add another chunk of Alka-Seltzer
  • When all the Alka-Seltzer is gone and the bubbling has completely stopped, screw on the bottle cap

How does it work?

Water and oil do not mix together, because water is a polar molecule and oil is a nonpolar molecule. Alka-Seltzer reacts with the water to make tiny bubbles of Carbon Dioxide and they attach to the colored water.  The bubbles rise to the top and pop.  The color blob then sinks down to the bottom. This keeps going until the Alka-Seltzer is gone.

From www.weirdsciencekids.com

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