Soap-boat-in-the-water

Soap-boat-in-the-waterUsing detergent to power a boat is a fun science experiment. You will learn to make a boat that runs only on detergent. Find out! How surface tension of water is affected to power your boat.

Things You will Need

  • A sheet of cardboard or Styrofoam
  • Liquid dishwashing soap
  • Dropper or Pencil
  • Scissors

How to Make

  1. Cut a sheet of cardboard into the shape of a boat; it should be 2 inches long and 1.5 inches.
    Soap Boat
  2. Make a triangular shaped notch in its back (as shown in the figure).
  3. Place your boat in a water tub, so that your boat has enough space to move.
  4. Place a drop of liquid dishwashing soap in the notch of your boat with dropper or pencil.

Now, watch your boat going around the tub! It will move forward.

How it Works?

Water molecules are attracted to each other, which creates surface tension in the water. Liquid dishwashing soap is a surfactant; it breaks down the surface tension of water. When you add liquid dishwashing soap in the notch, it breaks the surface tension of water inside the notch. As a result, it creates enough force to push the boat forward. We have used light material (e.g. Styrofoam or cardboard) to build the boat. Because, light materials can be easily pushed when surface tension breaks.

Try it

  1. Use different materials to build your boat and find out! Which material provides more speed?
  2. Can you rotate your boat without moving it forward or backward? Think about it.
Homemade Lava Lamp

Homemade Lava LampLava Lamp is an electric lamp which contains the brightly colored substance. This bright substance rise and falls while changing their shape. Lava lamps give a good background decoration and grasp the attention of people. So, here you will learn how to a make lava lamp. This lava lamp won’t require electricity to operate. All the materials you will find easily in your kitchen.

Things You Will Need

  • A clear empty plastic bottle
  • Vegetable oil
  • Food coloring
  • Water
  • Alka-Seltzer tablet (tablet that fizz)

How to Make

  1. Fill the bottle about a quarter with water.
  2. Fill the remaining space of the bottle with vegetable oil, and keep it aside for 5 minutes. When oil and water become separated from each other, then proceed to next step.
  3. Add few drops of food coloring of your choice in the bottle. It will take some time to break-through the oil and the water.
  4. Break the seltzer tablet into four pieces and drop one piece in the bottle. Watch it sinking to the bottom.

When seltzer tablet will touch the water your lava lamp will start to work. When bubbles stop to form add another piece of seltzer tablet to water.

ENJOY!

How it works

When oil and water are mixed, they form two layer. The oil settles at the top, and water at the bottom. Because, oil is less dense than water, so it floats on water. When you drop the seltzer tablet to bottle it goes to water layer and starts to form bubbles by a chemical reaction. These bubbles go up taking some colored water with them. At the top of the bottle, air escapes and leaves the water behind, which falls back down. Doing so it creates a nice effect of a lava lamp that you enjoy.

Try It

  1. Try to make seven lava lamps with rainbow colors and start them at the same
upside down glass

upside down glassCan you keep the water from falling down? Let’s make an experiment using simple household materials and try to defy gravity. We will try to hold the water in an upside-down glass and keep it from falling. Also, you will understand the science behind it.

Things You Will Need

  • Empty Glass
  • sheet Cardboard (that covers the mouth of glass)
  • Water

Procedure

  1. Fill the glass with water completely.
  2. Take a flat sheet of cardboard and place it over the mouth of the glass.
  3. Hold the cardboard with the glass tightly, then quickly upside down the glass.
  4. Slowly take away your hand that is holding the cardboard.

If all goes correctly, then the cardboard will stick to the mouth of the glass. The water will not fall from it.

What is Happening?

So, you’re thinking what is happening here! It all happens due to the absence of air in the glass. As a result, the pressure of outside air is much greater than inside of the glass. So, outside is forcing the cardboard to stay in its place. Which in turn, keeps the water from falling.

Try it

  1. Try to use different kinds of paper sheets and use it in the place of the cardboard for hold the water. Observe which paper sheet is able to hold the water.
  2. Use glasses with the wide and narrow mouth, and find out which is easier for this experiment.
home-made-flubber

home-made-flubberHave you watched Flubber movie 1997? If yes, then you know that in this movie Robin William makes a green rubber-like substance named “Flubber”. In this experiment, we will make flubber (It won’t talk! SORRY!) But you can play with it. You will also understand the science behind it.

Precaution: Always wear safety goggles and hand gloves when dealing with chemicals. Also, take the permission from your parents for the experiment, or involve them.

Things You Will Need

  • Warm Water
  • 1 cups of Elmer White Glue
  • 2 tablespoons of Borax
  • Green Food Coloring
  • Airtight bag

How to Make

  1. Pour ¾ cup of warm water and 1 cup of white glue in a bowl.
  2. Add 2 to 3 drops of food coloring in the bowl and stir the mixture with a spoon
  3. Pour ½ cup of warm water in another bowl, and add 2 tablespoons of borax in it. Stir the solution to completely mix the borax with
  4. Pour all the solution of borax in the first bowl, and stir the mixture well with a spoon.
  5. Pour all content of bowl in an airtight Close the bag tightly and make sure no liquid is leaking from the bag.
  6. Knead the mixture in the bag with your hands from outside for 5 to 10 minutes.

Your flubber is ready!

You can remove it from the bag and play with it. If your flubber is sticky then let it dry a little bit, then it will be okay.

How it Works

The flubber you made is a Polymer. You made it by mixing borax and glue together. Borax acts as a connector (crosslinking agent) for the glue molecules. When glue molecules are joined together and formed a large molecule chain you got a gel-like substance.

Try it

  1. Try to make a rainbow flubber. You can make it by preparing seven different flubber, but kneading all the seven flubbers together when they are still sticky.
inflating balloon

inflating balloonInflating the balloon with vinegar and baking soda is a classic experiment. Perform this experiments with your friends, and explain to them what is happening? You won’t need to buy anything, all the materials you will find in your kitchen easily.

In this experiment, you will learn how the gas (carbon dioxide) produced from chemical reaction inflates the balloon.

Precaution: Always wear safety goggles and hand gloves when dealing with chemicals. Also, take the permission from your parents for the experiment, or involve them.

You Will Need

  • An empty plastic bottle
  • A Half-Cup of Vinegar
  • A Balloon
  • 2 to 3 Spoons of Baking Soda
  • Water

Procedure

  1. Pour the half cup of vinegar and one-fourth cup of water in the plastic bottle.
  2. Inflate and deflate the balloon with your mouth 2 times to make it lose.
  3. Pour 2 spoonful of baking soda into the balloon using a funnel (If you don’t have a funnel, you can make one from paper and scotch tape).
  4. Stretch open the mouth of the balloon, and carefully put it over the neck of the plastic bottle. Let the end of the balloon dangle to prevent the baking soda from falling into the bottle.
    Balloon with baking soda

Your inflating balloon is ready!

When you want to inflate the balloon just hold the mouth of balloon tightly on the neck of the bottle. Then, let the baking soda in the balloon to fall in the bottle.

Now, observe the inflating balloon and chemical reaction.

What is Happening?

When the baking soda is added to vinegar, an acid-base reaction takes place. In this reaction, carbon dioxide gas is produced which develops pressure inside the bottle and starts to inflate the balloon. The balloon is being inflated with carbon dioxide gas, so it won’t float in the air. Because carbon dioxide is heavier gas than air.

Try It

If you want to slow down the reaction, so that balloon inflates slowly. Just, add water to the bottle to dilute the vinegar.