Any type of experiment whether a large scale scientific research project or performed in a small high school classroom should be performed with the proper safety precautions. When performing any kind of chemistry experiment in the classroom it is essential that students use the right safety equipment and understand the proper procedures to avoid serious injury. Students should always be sure to have permission to do any kind of experiments first while using chemicals.
Certain chemicals when mixed together can cause explosive reactions and can be irritating to the eyes, mouth, and lungs. If certain chemicals are spilled they can cause skin problems and other serious issues. While performing any kind of experiment with chemicals, eye protection should always be worn. There is an excellent collection of school experiments are as follows.
Baking Soda and Vinegar Volcano
The baking soda and vinegar volcano is the kitchen equal of a volcano. It is not a real volcano. The baking soda volcano is also harmless which adds to its application.
What You Needed:
- 6 cups flour
- 2 cups salt
- 4 tablespoons cooking oil
- Warm water
- Plastic soda bottle
- Dishwashing detergent
- Food colouring
- Baking dish or other pan
- 2 T baking soda
Time required for the experiment: 30 minutes
Make the cone of the baking soda volcano. Mix 6 cups flour, 2 cups salt, 4 tablespoons cooking oil and 2 cups of water. The resulting mixture should be smooth and firm.
Stand the soda bottle in the baking pan and mould the dough around it into a volcano shape. Don’t cover the hole or drop dough into it.
Fill the bottle most of the way full with warm water and a bit of red food colour (don’t take so long that the water gets cold).
Add 6 drops of detergent to the bottle contents. The detergent helps trap the bubbles produced by the reaction so you get better lava.
Add 2 tablespoons baking soda to the liquid.
Slowly pour vinegar into the bottle.
Tips for best Results:
The cool red lava is a chemical reaction between the baking soda and vinegar.
Carbon dioxide gas is produced which is also present in real volcanoes.
As the carbon dioxide gas is produced, pressure builds up inside the plastic bottle, the gas bubbles out of the ‘volcano’.
Adding a bit of food colouring will result in red-orange lava. Orange seems to work the best. Add some red, yellow, and even purple, for a bright display.
Elephant Toothpaste Chemistry Demonstration
The elephant toothpaste chemistry demonstration is a dramatic demo which produces plentiful amounts of hot foam that sort of looks like the toothpaste an elephant might use.
Elephant Toothpaste Materials
- 50-100 ml of 30% hydrogen peroxide (H2O2) solution
- Saturated potassium iodide (KI) solution
- Liquid dish washing detergent
- Food colouring
- 500 ML graduated cylinder
- Splint (optional)
Wear disposable gloves and safety glasses. Oxygen is evolved in this reaction. The reaction is exothermic, producing a fair amount of heat, so do not lean over the graduated cylinder when the solutions are mixed. Leave your gloves on following the demonstration to aid with cleanup. The solution and foam may be rinsed down the drain with water.
Put on gloves and safety glasses. The iodine from the reaction may mark surfaces so you might want to cover
Your work space also needed an open garbage bag or a layer of paper towels.
Pour 50 ml of 30% hydrogen peroxide solution into the graduated cylinder.
Shoot in a little dish washing detergent and spin it around.
You can place 5-10 drops of food coloring along the wall of the cylinder to make the foam resemble striped toothpaste.
Add 10 ML of potassium iodide solution. Do not slant over the cylinder when you do this, as the reaction is very strong and you may get splashed burned by steam.
You may touch a glowing support to the foam to relight it indicating the presence of oxygen.
Elephant Toothpaste Chemistry
The overall equation for this reaction is:
2 H2O2 (aq) ? 2 H2O (l) + O2 (g)
The decomposition of the hydrogen peroxide into water and oxygen is catalyzed by the iodide ion.
H2O2 (aq) + I-(aq) ? OI-(aq) + H2O (l)
H2O2 (aq) + OI-(aq) ? I-(aq) + H2O (l) + O2 (g)
The dishwashing detergent captures the oxygen as bubbles. Food colouring can colon the foam. The heat from this exothermic reaction is such that the foam may steam. If the demonstration is performed using a plastic bottle you can expect small bend of the bottle from the heat.
What You Needed:
- 5 or more litres of liquid nitrogen
- Gloves and goggles recommended
- Large plastic or stainless steel punch bowl or salad bowl
- 4 cups heavy cream (whipping cream)
- 1-1/2 cups half-and-half
- 1-3/4 cups sugar
- 1 quart mashed fresh strawberries or thawed frozen berries
- Additional half cup of sugar if you are using unsweetened berries
- Wooden spoon
- Wire whisk
How to Make Liquid Nitrogen Ice Cream
You can use liquid nitrogen to make ice cream much immediately. This recipe is for strawberry ice cream. If you pass over the strawberries you can add a bit of vanilla for vanilla ice cream or some chocolate syrup for chocolate ice cream. This recipe makes a half gallon of strawberry ice cream.
First, mix the cream, half-and-half and sugar in the bowl using the cord whisk. Continue mixing until the sugar has dissolved.
If you are making vanilla or chocolate ice cream, whisk in vanilla or chocolate syrup now. Add any other liquid flavouring you might want.
Put on your gloves and goggles. Pour a small amount of liquid nitrogen directly into the bowl with the ice cream ingredients. Continue to stir the ice cream, while slowly adding more liquid nitrogen. As soon as the cream base starts to thicken, add the mashed strawberries. Stir energetically.
When the ice cream becomes too thick for the whisk, switch to the wooden spoon. As it hardens more, remove the spoon and just pour the remaining liquid nitrogen onto the ice cream to fully harden it.
Allow to excess liquid nitrogen to boil off before serving the ice cream.
Tips for best Result:
The mix of whipping cream and half-and-half helps to make a very creamy ice cream with small crystals that freezes quickly.
Don’t touch liquid nitrogen or store it in a closed container.
If the ice cream begins to melt before everyone is served, simply add more liquid nitrogen.
A large plastic mug with a handle is good for pouring the liquid nitrogen. If you use a metal container, be sure to wear gloves.
Mixing attachment is even better than a whisk and wooden spoon.
Rubber Egg & Chicken Bones
You can make a toy out of just about anything, including a boiled egg. Soak an egg in a common kitchen ingredient, vinegar, to dissolve its shell and make the egg rubbery enough that you can bounce it on the floor like a ball. Soaking chicken bones in vinegar will soften them so that they will become rubbery and flexible.
Rubber Egg Materials Required
- hard-boiled egg
- glass or jar, big enough to hold the egg
Now Turn the Egg into a Bouncy Ball
Place the egg in the glass or jar.
Add enough vinegar to completely cover the egg.
Watch the egg. Little bubbles may come off the egg as the acetic acid in the vinegar attacks the calcium carbonate of the eggshell. Over time the colour of the eggs may change as well.
After 3 days, remove the egg and gently rinse the shell off of the egg with tap water.
You can soak raw eggs in vinegar for 3-4 days, with a slightly different result. The eggs shell will become soft and flexible. You can gently squeeze these eggs but it’s not a great plan to try to bounce them on the floor.
Make Rubbery Chicken Bones
If you soak chicken bones in vinegar, the vinegar will react with the calcium in the bones and weaken them so that they will become soft and rubbery, as if they had come from a rubber chicken. It is the calcium in your bones that makes them hard and strong.
- 1/4 cup of baking soda
- 1 cup of vinegar
- bubbles and a bubble wand (you can get this at most toy stores)
- 2 large, clear containers, like a clear plastic or glass bowl
- small clear cup
Put 1/4 cup baking soda in a clear container.
Then add 1 cup of vinegar.
The mixture of vinegar and baking soda will bubble. It is carbon dioxide.
Blow some bubbles into the container and watch how they float on the carbon dioxide. The bubbles are floating where the carbon dioxide and air meet.
The carbon dioxide stays at the bottom of the bowl because it is denser than the air in the bowl. The bubbles float on top of the carbon dioxide because they are filled with air and the air is less dense than the carbon dioxide.
This will help explain what density means. Pretend that you had two balloons and you filled one with air, and the other one with the same amount of carbon dioxide. The balloons would be the same size, because the gas in them takes up the same amount of space.
But, if you weighed both balloons, the one with the carbon dioxide would be heavier. This means that it’s denser than the balloon with air in it.
If you still don’t understand density, don’t worry. There are lots of people out there who can answer your questions. Talk to your teacher, go to a science museum, visit your local library, or ask your parents.
Fizzing and foaming
With a few household chemicals you can turn a glass of colored liquid into foam that overflows its container.
For this experiment you will need:
- 15 cm3 (1 tablespoon) of baking soda (sodium bicarbonate)
- 15 cm3 (1 tablespoon) of laundry detergent
- about 180 millilitres (3/4 cup) of water
- about 60 millilitres (1/4 cup) of vinegar
- several drops of food colouring (optional)
- a 400-milliliter (12-ounce) drinking glass
- a waterproof (plastic or metal) tray
- a teaspoon
Place the drinking glass on the tray. Put 15 cm3 baking soda and 15 cm3 laundry detergent to the glass. Add 180 ml of water and a few drops of optional food colouring. Gently stir the mixture to mix the contents of the glass. To display and observe the fizzing and foaming, quickly pour the vinegar into the glass. The mixture will foam up and over the top of the glass, covering the tray with foam of tiny bubbles.
To produce a colour change when the vinegar is added to the mixture in the glass, you can replacement some red cabbage juice for the optional food colouring. For a different colour change, try grape juice.
In this experiment the fizz is produced by a chemical reaction between baking soda and vinegar. Baking soda and vinegar react and one of the products of the reaction is carbon dioxide gas. This gas forms bubbles that are surrounded by the liquid. The laundry detergent makes the bubbles last longer and foam is produced. The volume of the gas produced and attentive in the foam is much greater than the glass can hold so some of it spills over the top of the glass.
Baking soda is sodium bicarbonate. Vinegar contains acetic acid dissolved in water. Sodium bar carbonate reacts with most acids. The products of the reaction with vinegar are carbon dioxide gas, sodium acetate and water. The reaction of sodium bicarbonate to form carbon dioxide gas is the basis of its use as a livening agent in baking. The foam is produced when bubbles of carbon dioxide from the reaction of sodium bicarbonate are intent. As the cake bakes, the bang dries and the intent bubbles of carbon dioxide form the holes in the cake.