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Showing posts from December, 2017

Dancing Spaghetti

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Materials Large beaker 150ml graduated cylinder 50ml cups of vinegar 2 tsp baking soda 50ml water  8-10 sticks of broken spaghetti. Food colouring  Procedure Fill the beaker with water  Measure and pour 100 ml of vinegar into the beaker. add the food colouring - if needed Add two tablespoons of baking soda to the water and mix thoroughly. Put eight to ten pieces of broken spaghetti in the beaker and wait until the spaghetti settles to the bottom. A chemical reaction will take place, causing the spaghetti to move in the beaker.  Repeat experiment with different ratios of water, vinegar, and baking soda. Whats happening The noodles will bob up and down for several minutes. This noodle “dance” is captivating to watch. Since the surface of the noodles is rough, tiny bubbles of carbon dioxide gas are attracted to it. These bubbles increase the volume of the noodle substantially, but contribute very little to its mass. As a result, the overall density of

JACK O’ LANTERN SLIME

Perfect  Halloween play with Jack O Lantern slime ! THE SCIENCE BEHIND THE HOMEMADE JACK O LANTERN SLIME RECIPE What’s the science behind the slime? The borate ions in the slime activator {sodium borate, borax powder, or boric acid} mixes with the PVA {polyvinyl-acetate} glue and forms this cool stretchy substance. This is called cross linking! The glue is a polymer and is made up of long, repeating, and identical strands or molecules. These molecules with flow past one another keeping the glue in a liquid state. Materials Clear Glue ( from any hobby shop) Liquid Starch   {or borax } Water 1/2 cup measure, spoons, and 2 containers for mixing Jack O’ Lantern table scatter {or what ever you find!} Procedure   In one bowl   mix 1/2 cup water and 1/2 cup of glue  {really mix to combine completely}. Pour glue into water. Stir the glue and water together well! Now’s the time to add colour, glitter, or confetti! Remember when you add colour to white glue, the colo

ICY CHRISTMAS TREE

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How many ways can you engineer a Christmas tree! This  icy Christmas tree STEM project  was super fun. We had a great time piecing together this icy Christmas tree before it melted.  Materials Different size containers  Water Food colouring Tinsel {optional} Procedure Freeze water in each of the containers.  Mix in green food colouring and add tinsel for a  more festive look. You can also dump in glitter and other Christmas themed objects for melting out later!  Next, prepare a surface for the icy tree parts. Use a large cookie sheet and put some parchment paper down. A sturdy piece of cardboard could also work. You may want to transfer to a bin after if you want to melt the ice with warm water. When frozen, remove the ice blocks and get started. You can put on gloves if you want to. Try squirting a bit of warm water will help set them in place better. This can be tricky, so you have to work on creating a stable base and use your building skills to get your tree

Doodle for Google

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This year for hour of code, I got my students to do the Doodle for Google coding in scratch. They thoroughly enjoyed they programming and learnt new concepts of how coding works. Have a go yourself. Follow this link: Doodle for Google in Scratch

Crystal Snowflake Ornament

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Make your own crystal snowflake ornaments by crystallising borax onto homemade paper snowflakes. These sparkling snowflakes can be made in any size to suit your decorating needs. MATERIALS  round paper coffee filters borax water scissors food colouring (optional) MAKE CRYSTAL SNOWFLAKE ORNAMENTS Cut a paper snowflake (or other shape) from the coffee filter. Prepare crystal solution by stirring borax into boiling water until no more will dissolve. You'll know the solution is ready if borax powder starts to accumulate on the bottom of your container. Add a drop of food colouring, if you want coloured snowflake ornaments. Place the paper snowflake onto a plate or saucer. Pour the crystal solution over the snowflake, making sure it is completely covered. Allow crystals to grow on the snowflake until you are satisfied with their size. Small crystals take about an hour to form. You can allow the crystals to grow overnight if you want larger crystals. Pour off the

Mystical Cloud

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Making a cloud inside a bottle may help you figure out how they form outside in the sky. Warm, moist air rises in the atmosphere, cools, and beautiful, puffy clouds can be the result. Tiny water droplets become clouds of many different kinds at many different altitudes depending on the conditions. Making your own cloud in a bottle is a popular activity in many science books but it can be a little tricky to pull off.  Materials Rubber gloves Eye protection A graduated cylinder An opaque bottle A  rubber stopper  or bottle cap A tea bag 50 ml 30% hydrogen peroxide 1/4 tbsp Potassium chloride.  Procedure Put on your rubber gloves and safety goggles before you start the experiment.  Pour 50 ml of 30% hydrogen peroxide into the opaque bottle and cap the bottle.  Carefully open the tea bag and remove the tea leaves.  Put one-quarter tbsp of potassium chloride to the tea bag and tie it close leaving enough string to overlap the lip of the bottle.  When you are r

CHRISTMAS TREE ELEPHANT TOOTHPASTE

The toothpaste demo is one of the most popular chemistry demos, in which a steaming tube of foam keeps erupting from its container, resembling a smooshed tube of elephant-sized toothpaste.  ELEPHANT TOOTHPASTE MATERIALS Erlenmeyer flask (If you don't have access to chemistry glassware, you can make a tree shape by inverting a funnel over a glass or making your own funnel using paper and tape (which you could decorate, if you like)) 3% hydrogen  peroxide solution  (available at nearly any store) Packet of active yeast  Liquid dishwashing detergent Warm water Green food colouring MAKE ELEPHANT TOOTHPASTE Pour 1/2 cup hydrogen peroxide solution, 1/4 cup dish washing soap, and a few drops of food colouring into the bottle.  Swish the bottle around to mix the ingredients. Set the bottle in a sink or outdoors or some other place where you won't mind getting wet foam everywhere. In a separate container, mix a packet of active yeast with a little warm wate

Gummy Bears on Fire!

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As this was more fun to do then video, we found an old video on YouTube to give a demonstration. This was fun, exciting and awesome to do!! In this experiment, a demonstration of a spontaneous exothermic reaction will take place between a gummy bear and molten potassium chlorate. Once the potassium chlorate has been melted in a test tube, a gummy bear will be dropped to his doom and flames will burst out of the tube as a result. Materials:  1. Safety first! Wear safety glasses  2. Plastic Shield  3. Gummy Bears  4. Potassium Chlorate (About 5-7 grams)  5. Pyrex Test Tube  6. Ring Stand with Clamp  7. Bunsen Burner  8. Matches  9. Tongs  10.Fume Hood or Snorkel Safety:  WARNING! Do not stand near experiment, and always remain on the outside of the fume hood. Viewers must stay behind demonstrators at all times for safety precautions. Those who are sensitive to light should avoid this demonstration.  Procedure:   Pour about 10g of Potassium

Briggs-Rauscher Reaction

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Having fun as always in my chemistry lab!!This with 15-17 year olds in a workshop INTRODUCTION The Briggs-Rauscher reaction, also known as 'the oscillating clock', is one of the most common demonstrations of a chemical oscillator reaction.  The reaction begins when three colourless solutions are mixed together. The colour of the resulting mixture will oscillate between clear, amber, and deep blue for about 3-5 minutes. The solution ends up as a blue-black mixture. SOLUTIONS Solution A: Add 43 g potassium iodate (KIO 3 ) to ~800 ml distilled water. Stir in 4.5 ml sulfuric acid (H 2 SO 4 ). Continue stirring until the potassium iodate is dissolved. Dilute to 1l. Solution B: Add 15.6 g malonic acid (HOOCCH 2 COOH) and 3.4 g manganese sulfate monohydrate (MnSO 4  . H 2 O) to ~800 ml distilled water. Add 4 g of cornstarch. Stir until dissolved. Dilute to 1l. Solution C: Dilute 400 mL of 30% hydrogen peroxide (H 2 O 2 ) to 1 L. MATERIALS 300 mL of each

Betty, the robot cleaner

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Introduction:  In this tutorial you ill learn what is a circuit.  An electric  circuit  is like a pathway made of wires that electrons can flow through. A battery or other power source gives the force (voltage) that makes the electrons move. ... The wires  have  to go from the power source to the device and back again, so that the electrons can go out and come back . Aim:  To build a  mini-robot that will help someone clean a tiny area in their home. (maybe you can create a big robot) Materials:  2 x bits of wire,  1 x 3v motor,  1 x AA battery,  3 x beads (a third one too if wanted),  2 x pieces of foamboard (or more if desired),  Some legs, A Hot Glue Gun. Method: 1. Connecting to your Motor:  You can either “twist” them on or solder them on. Soldering will probably give your little robot more longevity, but isn’t strictly necessary. Take your pieces of wire and solder one of each onto a metal contact on the motor. This is quite fiddly so be careful