1. Density Column Materials

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1 1. Density Column Materials Honey - golden corn syrup- clear liquid dishwashing soap- blue water (can be colored with food coloring) vegetable oil - yellow rubbing alcohol (can be colored with food coloring) lamp oil- red Make the Density Column Pour your heaviest liquid into the center of whatever container you are using to make your column. If you can avoid it, don't let the first liquid run down the side of the container because the first liquid is thick enough it will probably stick to the side so your column won't end up as pretty. Carefully pour the next liquid you are using down the side of the container. Another way to add the liquid is to pour it over the back of a spoon. Continue adding liquids until you have completed your density column. At this point, you can use the column as a decoration. Try to avoid bumping the container or mixing its contents. The hardest liquids to deal with are the water, vegetable oil, and rubbing alcohol. Make sure that there is an even layer of oil before you add the alcohol because if there is a break in that surface or if you pour the alcohol so that it dips below the oil layer into the water then the two liquids will mix. If you take your time, this problem can be avoided. How the Density Column Works You made your column by pouring the heaviest liquid into the glass first, followed by the next-heaviest liquid, etc. The heaviest liquid has the most mass per unit volume or the highest density. Some of the liquids don't mix because they repel each other (oil and water). Other liquids resist mixing because they are thick or viscous. Eventually some of the liquids of your column will mix together.

2 2. The Floating Egg Two drinking glasses Two raw eggs Table salt Spoon Fill one of the drinking glasses almost to the top with plain tap water. Gently drop one of the eggs into the water-filled glass. It sinks right to the bottom! Fill the second drinking glass half-full with water. Add four tablespoons of table salt to the water, and stir. Fill the rest of the cup with water, almost to the top. Gently place the second egg into the salt water solution it floats! All you did was add salt to your water. How in the world does the second egg float? The first egg sinks to the bottom of the glass of regular tap water. This is because a raw egg has a greater density than regular tap water. Essentially, the egg has more matter stuffed into a specific area (volume) than the same amount of water. When you add salt to the water, you increase the density. That is to say, the salt packs into the same volume of water. With enough salt added to the water, the density of the water is greater than the egg, allowing the egg to float.

3 3. Dancing Spaghetti Materials Large vase(s) (inch) Pasta noodles cooked Water Vinegar Baking soda Food coloring Various small objects Measure/add 2 Cups of water to vase Add 2 Cups of vinegar 4 drops of food coloring Add spaghetti Add 1 Table spoon of Baking soda When reaction is done add more Baking soda When baking soda and vinegar are mixed together, a chemical reaction occurs. It produces a gas called carbon dioxide, which forms lots of bubbles on top of the mixture and smaller bubbles at the bottom of the glass. These little bubbles stick to the spaghetti and make it float to the surface, just as you do when you sit on a swimming pool noodle! When the spaghetti reaches the surface, the bubbles pop and the spaghetti sinks to the bottom.

4 3. CO2 Fire Extinguisher White vinegar Baking soda Clear container Candle(s) Lighter or matches Pour some baking soda into a clear beaker or glass. Add some vinegar into the mix by pouring white vinegar into the same container as the baking soda. Whoa that's a foamy reaction! Wait a few moments while the reaction tapers off. Use a lighter or matches to ignite the candle(s). Grab the container with what used to be vinegar and baking soda and slowly "pour" the air from the container. Be careful not to pour the liquid! As you move the container from candle to candle as you pour the air out, the flames will extinguish. No way! Most flames require oxygen, fuel, and sufficient heat to ignite and stay lit. These three components of fire are referred to as the fire triangle or combustion triangle. Removal of any of the three components will cause the flame to extinguish or "go out." The secret to extinguishing fire is the removal of one of the three components. In CO2 Fire Extinguisher experiment, that lies in the bubbling mixture in the container. The baking soda (also known as sodium bicarbonate) is a base. The vinegar, or acetic acid, is a weak acid. When baking soda and vinegar are combined, the immediate acid-base reaction creates carbonic acid. Carbonic acid is unstable and decomposes into carbon dioxide (CO2) and water (H2O). The bubbling that you see inside of the container is the production of the CO2 gas. When you "pour out" the container, you're exposing the flame to concentrated CO2 gas. The lack of oxygen extinguishes the flame. How can you possible pour a gas? The air that we breathe is comprised largely of nitrogen gas, a very light gas. The CO2 that was created inside of the cylinder is much heavier and, therefore, able to be poured like a liquid, out of the container.

5 BURN YOUR MONEY 70 ml alcohol 30 ml water salt Dollar bill TONGS flame Start by preparing a water-alcohol mixture by combining 70 ml of 70% rubbing alcohol with 30 ml of water. Make sure to stir the mixture thoroughly. Borrow a $20 bill from your friend. Rule #1: Never use your own money. Dip the bill into the mixture of water and rubbing alcohol, making sure the bill is completely soaked. Remove the bill using the tongs - squeeze out any excess liquid. Move the water-alcohol mixture to a safe place (away from the area where you are going to light the bill). Hold one end of the bill with tongs and light the bottom of the bill. The bill will look like it's burning, but it shouldn't burn (famous last words). When the flame is completely extinguished, it's safe to touch the money... you'll find that the money is even cool to the touch. Alcohol burns with an almost invisible blue flame. One trick is to add a little table salt to the water-alcohol mixture to make the flame more visible. By now you've probably guessed that the money will actually burn if you dip it into a pure alcohol solution. The secret, of course, is the addition of water to the mixture. The water from the water-alcohol mixture absorbs much of the heat energy that is generated when you ignite the bill. The temperature of the paper money does not rise above the temperature required to burn the paper. The water is first heated to its boiling point and then vaporized by the heat of combustion from the burning alcohol. If you reduce the amount of water in the mixture, the paper money is likely to char or even catch fire.