6th Grade Instant Replay
("Did I miss anything good when I was absent?")
Gum Experiment (the "Mass-tication" Investigation)
We investigated the following question: "How does chewing a piece of gum affect the gum's mass?" Each student selected a piece of gum, either sugarless or bubble gum. We measured each gum's beginning mass in the wrapper. Then students chewed their gum for 12 minutes, stopping every 2 minutes to measure and record their gum's mass.
We discovered the following facts:
• A typical piece of bubble gum, such as Bazooka, Bubblicious or Bubble Yum, has a beginning mass of around 8 grams.
• During the investigation, the bubble gums lost more than half their mass in about 8 minutes.
• By checking the gum ingredients, we found that these gums are about 75% sugar.
Our conclusion is that sugar is very quickly dissolved and swallowed during the chewing process. The remaining "gum" is mostly a piece of soft rubber that cannot be dissolved or digested.
• We also found that sugarless gums have a much smaller starting mass of about 3.5 grams. While their mass decreases a bit, the difference is not as great because they contain only a small amount of artificial sugar, which is difficult to dissolve.
We discovered the following facts:
• A typical piece of bubble gum, such as Bazooka, Bubblicious or Bubble Yum, has a beginning mass of around 8 grams.
• During the investigation, the bubble gums lost more than half their mass in about 8 minutes.
• By checking the gum ingredients, we found that these gums are about 75% sugar.
Our conclusion is that sugar is very quickly dissolved and swallowed during the chewing process. The remaining "gum" is mostly a piece of soft rubber that cannot be dissolved or digested.
• We also found that sugarless gums have a much smaller starting mass of about 3.5 grams. While their mass decreases a bit, the difference is not as great because they contain only a small amount of artificial sugar, which is difficult to dissolve.
Measuring Volume of a Rectangular Prism
Measuring Mass with a Triple-Beam Balance
Melting a Penny
Since 1982 the U.S. government has stopped making pennies from pure copper, because each penny cost far more than one cent to make. Pennies are now made of about 98% zinc, and 2% copper (which is just a thin coating on the outside to make the penny look like a penny!) Since zinc melts at a lower temperature than copper, you can heat a penny enough to turn the inside to liquid while the outside remains solid. (In the same way, M&M candies melt on the inside while the candy coating stays hard). The video below shows one way to "disassemble" a penny!
"Pouring Air" Experiment
Below are some videos of students performing the "Pouring Air" experiment. We use acetic acid (vinegar) and sodium bicarbonate (baking soda) to create a chemical reaction that produces carbon dioxide. Since CO2 is heavier than air, the invisible heavy gas pushes oxygen away from the candle, causing the flame to go out. It's not magic- it's SCIENCE!
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Colored Flames Demonstration |
When some metals are made into fine powder and burned in a flame, they give off brilliant colors. This is what gives fireworks their beautiful hues. In the demonstration below, different chemical "salts" (chlorides) were burned to make colorful flames.
Observation Stations
Students visited 5 different stations where they tested their ability to make scientific observations and inferences, using each of the five human senses.
Usually, we use a combination of senses to make observations; for example, we can see and smell the food we are tasting. The trick in this activity is to isolate each of the senses as much as possible, as you will see in the video below.
Usually, we use a combination of senses to make observations; for example, we can see and smell the food we are tasting. The trick in this activity is to isolate each of the senses as much as possible, as you will see in the video below.
Is it Magic? Or is it Science? |
What is the difference between magic and science? Every "magic" trick is really just a science demonstration. The great science fiction author, Arthur C. Clarke, said it like this: "Any sufficiently advanced technology is indistinguishable from magic." That means it only looks like magic if you don't understand science.
In the demonstration below, if you DON'T understand science, it appears that water can magically change to different colors, and then vanish when poured into a styrofoam cup.
But those who understand science will recognize this as a chemical reaction between an acid (vinegar), a base (ammonia) and color-changing "indicator" solutions (phenolphthalein and thymolphthalein). So what happened to the water in the styrofoam cup? It's still in there, of course! A small amount of super-absorbent polymer (sodium polyacrylate) absorbed the water to create a solid jell-like material. (This is the same powder that makes a baby diaper so absorbent!)
In the demonstration below, if you DON'T understand science, it appears that water can magically change to different colors, and then vanish when poured into a styrofoam cup.
But those who understand science will recognize this as a chemical reaction between an acid (vinegar), a base (ammonia) and color-changing "indicator" solutions (phenolphthalein and thymolphthalein). So what happened to the water in the styrofoam cup? It's still in there, of course! A small amount of super-absorbent polymer (sodium polyacrylate) absorbed the water to create a solid jell-like material. (This is the same powder that makes a baby diaper so absorbent!)