Dancing spaghetti - Proven Demonstrations PDF

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Demonstration Title: Dancing Spaghetti Curriculum Context (from BC IRP): Science 9: Physical Science - Atoms, elements and compounds C4 describe changes in the properties of matter Science 10: Physical Science - Chemical Reactions and Radioactivity C2 classify substances as acids, bases, or salts, based on their characteristics, name, and formula Chemistry 11: Chemical Reactions D3 devise balanced equations for various chemical reactions Materials: 1-1000mL beaker or 1 mixing bowl 3 tsp. of baking soda 4-5 Tbsp. of vinegar ~10 - 2cm pieces of vermicelli or spaghetti noodles Safety: Ensure not to add too much baking soda and vinegar, this can result overflowing, make sure not to fill the bowl or contained full of water, ½ or ¾ is full enough. Note: This demonstration can also simply use a clear carbonated liquid, such as club soda. Directions: 1. Fill a clear bowl, ¾ fill with water 2. Add baking soda (Base), and stir to dissolve. 3. Break the spaghetti noodles into 2cm pieces and add them to the mixture. 4. Next add the vinegar (acid). Notes: If the noodles do not start to dance after a few minutes, add more baking soda and vinegar Add on: sub raisins or mothballs instead of noodles. Questions: Before the demo starts:  Does anyone know what baking soda and vinegar are?  What do you think will happen, when we put the vinegar and baking soda together?  What do you notice when I put the noodles in the water/baking soda? Do they sink or float? Why? After:  What do you think happened?

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Why do you think the noodles started to float? Do you think that the noodle will ever sink again? Could we use anything else to besides the noodles?

Explanation: In this demonstration, vinegar (acid) and baking soda (base) are added to water. The baking soda is added the water and then the noodles are added, from this you can obviously see that the noodle are more dense than the water, baking soda mixture therefore sinking to the bottom. When the vinegar is added to the mixture, there is an obvious chemical reaction, creating foaming and bubbling; this results in carbon dioxide, water and sodium acetate being formed. The carbon dioxide bubbles attach to the uncooked noodles and slowly move around the mixture, eventually floating to the top. Below is the reaction between vinegar & baking soda, an acid/base reaction: NaHCO3 (aq) + HC2H3O2 (aq) ------> CO2 (g) + H2O (l) + NaC2H3O2 (aq) This demonstration can be used for a variety of grade levels in science, as it has multiple concepts in it. In the BC IRP, this would fit into Science 9, when they discuss density, when you put in the noodles in the mixture, why do they sink at first? In Science 10, students learn about acid/base reactions, this demo would be a good way to start the class out, by showing the formula on the board you could discuss why each one is an acid and base. Finally it could be used in Chemistry 11, when they balance equations, this could be a bonus question for students that are having an easy time....