National Science Week is Australia’s annual celebration of science and technology. To help celebrate we have we have gone beyond the science classroom and put together a three simple science experiments for kids you can try at home knowing you probably already have most of the materials just lying around the house.
Here are a few simple ways for you to see science in action.
Slippery Slime
WHAT YOU NEED
- 2 18 ml bottles Elmer's school glue
- 1 to 2 drops liquid food colouring (optional)
- 1 teaspoon baking soda
- 2 to 3 tablespoons contact lens solution
INSTRUCTIONS
- Step 1: Pour the glue into a bowl. (If you want to colour your slime stir in the food colouring now).
- Step 2: Add the baking soda to the glue mixture and stir until smooth.
- Step 3: Add 2 tablespoons of contact lens solution and slowly stir.
Note: The mixture will begin to harden and become stringy. - Step 4: Continue slowly mixing until a ball of slime forms.
Step 5: It's time to get hands on, pick up the slime and kneed it between your two hands, until smooth. If the slime is a little too slimy, massage in another 1/2 tablespoon of contact lens solution as needed.
TIP: Try adding 1/4 cup biodegradable glitter in Step 1 to make your slime sparkle and shine!
THE SCIENCE
Glue has something called polyvinyl acetate in it, which is a liquid polymer. The baking soda and saline solution links the polyvinyl acetate molecules to each other, creating one large, flexible polymer that we call slime!
Tornado in a bottle
WHAT YOU NEED
- Tap water
- A clear plastic bottle with its cap
- Biodegradable glitter
- Dish washing liquid
INSTRUCTIONS
- Step 1: Fill the plastic bottle with water until three quarters full.
- Step 2: Add a 5-6 drops of dish washing liquid to the water.
- Step 3: Sprinkle in a few pinches of bio degradable glitter (this helps make your tornado easier to see).
- Step 4: Screw the cap of your bottle on tightly. Turning the bottle upside down, hold it by the neck and quickly spin the bottle in a circular motion for a few seconds. Stop and look inside to see if you can see a mini tornado forming in the water.
TIP: Try using a Vortex Valve to take your tornado to the next level!
THE SCIENCE
As you spin the bottle in a circular motion it creates a water vortex that looks like a mini tornado. Centripetal force causes the the water to spin rapidly around the centre of the vortex.
Centripetal force is an inward force directing an object or fluid such as water towards the centre of its circular path. Vortexes found in nature include tornadoes, hurricanes and waterspouts!
Lava Lamp
WHAT YOU NEED
- Water
- Food colouring
- A clear plastic bottle with its cap
- Baby oil
- Fizzing tablets
INSTRUCTIONS
- Step 1: Fill your bottle 1/3 of the way with water
- Step 2: Add a couple of drops of food colouring to the water. Gently swirl the bottle to mix the colour.
- Step 3: Slowly add the baby oil to the bottle. You want to add roughly the same amount of baby oil as water.
TIP: Tilt your bottle as your pour in the oil so it runs down the side of the bottle to help keep the two solutions separated. If you poor he oil directly into the water you may need to wait a few minutes for the solutions to separate. - Step 4: Break the fizzing tablet in half (to help your tablet fit through the bottle neck) and drop both halves into the solution. Watch as your lava lamp starts to bubble and boil!
Checkout the video from Science Fun For Everyone! to see the lava lamp in action!
THE SCIENCE
The oil floats on top of the water because it is less dense or lighter than water. The food colouring has the same density as the water so it sinks through the oil and mixes with the water. When you add the tablet it sinks to the bottom then starts to dissolve. As it dissolves it makes gas, carbon dioxide. Gas or air is lighter than water so it floats to the top. The air bubbles bring some coloured water with them to the top. When the air comes out of the coloured water blob, the water gets heavy again and sinks. It does this over and over again until the tablet is completely dissolved.
Source: Science Fun For Everyone