Science Fun

Some Chemical reactions produce heat and light, a candle burning is one such example as you have light from the flame as well as the heat produced by the flame.  It is not as common for a chemical reaction to produce the light without producing heat.  There are some examples of chemical reactions that produce light without heat and one of them is a living organism, the Firefly. 

Modern technology has produced something that many of us are familiar with and that is the light stick.  A plastic tube that contains chemicals, that when activated, the light stick glows or produces light.  Here are few fun things you can do to experiment and learn about the light stick.  So go find a light stick at a hobby shop, outdoor sports shop, or even at most dollar stores.

Follow the directions on the light stick wrapper to activate it – most of them, you are bending them to break an inner glass vial, then you shake them to mix the chemicals and they begin to glow.   First, go into a dark room and observe your light stick – what color is the glow?  Does the glow come from the entire stick or just the chemical within the stick.

Now, grab a glass of ice water and immerse the light stick into the water.  Does the chilling effect of the water affect the glow?  What happened to the glow?  Now, get a glass of warm water (not boiling) and immerse the light stick in the warm water – what did you observe about the glow?

Take a break for a day – throw the light stick in your freezer and comeback to it in 24 hours.  Is it still glowing?  Remove the light stick from the freezer, what happens to the glow of the light stick as it returns to room temperature?

In this fun little exercise, you played with the light stick in various settings, what changes did you observe in the glow?  What would you suggest to prolong the glow of the light stick?  In the light stick, the faster the reaction, the brighter the glow, thus, the chemical reactance will be used up faster and the light stick will not last as long.

Ever wonder what makes soda fizz? It is a gas, and the name of that gas is – Carbon Dioxide. In the manufacturing process, the carbonated beverage is packed in cans or bottles under high pressure, using carbon dioxide. This gas is dissolved into the beverage due to the pressure, when you open the container, the noise you hear is the rush of the gas escaping from the container, the beverage gets bubbly due to the gas escaping from the beverage.

Here is a fun little experiment – make raisins dance! You will need a tall glass, a can of clear soda such as Sprite or 7-Up, and several raisins. Pour the soda into the tall glass – notice the bubbles rising to the top – that is the carbon dioxide gas. Now, drop several raisins into the glass – what happened?

At first the raisins sank to the bottom of the glass (they are denser than the beverage), then as the carbon dioxide bubbles adhere to the rough sections of the raisin, there will become enough of the little gas bubbles that will then have enough power to lift the raisin to the surface, then bubbles pop, the gas escapes into the atmosphere and the raisin sinks back to the bottom of the glass to begin the journey all over again. This process will continue until the soda goes flat (or the raisin gets so soggy, that it can not be lifted anymore).

Try other objects for this little experiment – the object has to have a rough surface and has to be just a little denser than water. What have you learned about Carbon Dioxide?

Do you have some old pennies that need a cleaning? Today, we will explore dirty pennies and how to get them all shined up again so they look like they just rolled off the mint. Pennies are manufactured with a coating of copper, they used to be all copper at one point, and then various metals were used, with zinc being the primary metal in today’s penny.

The copper outer layer of the penny; will over time, oxidize as a result of being exposed to the air, thus copper oxide is formed (the dull and greenish look). We will create a little solution whereby you can bathe the pennies and return them to their shiny appearance.

You will need ¼ cup of white vinegar, 1 teaspoon of salt, a clear glass or plastic bowl (not metal), and some water to wash the pennies after you pull them out of the bath. Mix the vinegar and salt in the bowl (until the salt dissolves) and then dump in the pennies you wish to clean. The cleaning action will be visible for a few minutes – leave the pennies in the solution for about five minutes. The acid of the vinegar will dissolve the copper oxide.

After about five minutes, the pennies will be nice and shiny – remove them from the solution and then wash them down in water to stop the solution from working – then dry them on some paper towels. Before you toss out your penny cleaning solution, you may wish to have a little bit of fun and make some copper coated nails – visit http://chemistry.about.com/cs/demonstrations/a/aa022204a.htm for a fun experiment using the solution you used to clean your pennies. You will also learn more about the oxidization and why it takes place. Enjoy and have fun!

Have you ever explored a cave and wondered what the ‘things’ are that grow from the ceiling of the cave downward, and upward from the floor. These are called “Stalactites” and Stalagmites”. Ok, which is which – a stalactite grows from the ceiling down and the stalagmite grows up from the floor.

Stalactites and Stalagmites form when water seeps its way through the ceiling of the cave and drips, when it drips, it leaves behind a mineral formation, which is the stalactite and as the water hits the floor, a mineral deposit from the water begins to build up over time, thus the stalagmite is formed. When a stalactite and a stalagmite touch, they form a column. A cave that is rich in limestone is one where these formations are most often found. There are just over 50 minerals that may cause the formation of stalactites and stalagmites in caves. They have a very slow rate of growth - 0.00028–0.037 in/yr.

Now that we have had a quick lesson on what they are, let us enjoy a fun science experiment using baking soda to create your own. For this exercise, you will need to round up the following:
• 2 glasses or jars
• 1 plate or saucer
• 1 spoon
• 2 paper clips
• Hot tap water
• 1 piece of yarn about 3 feet (cotton or wool, un colored if possible)
• Baking soda
• Food coloring if you desire to color your creation.

Fold the piece of yarn in half, then in half again, then tightly twist it. Attach the paper clips to each end of the yarn – this will support the yarn while it rests in the liquid. Next, position the glasses at opposite sides with the bowl or saucer in the center, then place your yarn over the glasses with the end in each glass, and allow it to sag slightly over the saucer or bowl. Next you will create your forming solution. Mix baking soda in hot tap water (add food coloring if you wish), saturating it to the point where you are not able to dissolve any more baking soda in the water. (The amount of mixture you will make depends on the size glasses you use – you will fill the glasses with the solution).

Pour the liquid into each glass – filling it right up. The liquid will begin to be absorbed by the yarn and will make its way through as time goes on – after a period of time you will begin to notice stalactites starting to form – going down towards the plate (watch the plate or bowl, it might begin to pool with water, keep it empty). The rate of growth of your creation will vary depending upon humidity, temperature, rate of evaporation, and the mixture. Have fun; try different variations of the mixture and even different types of yarn or string. Enjoy! Recipe from About.com and rate of growth statistic from Wikipedia.

Here is a fun exercise with crystals – sugar crystals.  You can make your own rock candy that you can eat and have fun while doing so.  Children, please ask for help from your parents as part of this exercise is working with hot liquids and the kitchen stove. 

So, first gather up your supplies.  You will need a sauce pan (or glass bowl for microwave), 1 cup of water, 3 cups of sugar (use white, granulated sugar that you would have for the table), a clean glass jar, pencil, string (yarn or rough string works well), spoon or rod for stirring, clean coffee filter or paper towel, and food coloring – choose your favorite color. 

You will need to boil the water in the sauce pan (if you use the microwave, be sure to use a glass bowl and not a metal pan).  Stir in the sugar (maybe a teaspoon at a time) until it accumulates at the bottom and will no longer dissolve, even with more stirring.  This means you will have a saturated solution to grow your crystals.  If you desire some color to your crystal, add in the food coloring at this time – just a few drops. 

Next, take the pencil and balance it across the top of the glass container, lower the string into the center of the container – be sure the string does not touch the sides or the bottom of the container (you will want the end of the string to be just above the bottom without touching).  Tie the string securely around the pencil and be sure it stays in the center.  Now remove the pencil and string until after you pour in your solution. 

Add the sugar solution to the glass jar; fill it up to about a ½ inch from the top.  If there are un dissolved sugar crystals at the bottom of your mixing container, be sure these do not end up in your jar.  Next, place the pencil over the jar of sugar solution and lower it down so the string will settle into the solution – keep it in the center.  Now, set your concoction aside in an area where it will not get disturbed.  You can place the coffee filter or paper towel over the top to keep out any dust or dirt. 

Check back in a day or so and you should start to see crystals forming to the string.  Let the crystals continue to grow until they get to the size you wish or when they stop growing.  Pull them out of the liquid and allow to dry.  Now you can eat them or save and enjoy them! 

Now, we can’t get away quite yet – time for a real quick chemistry lesson to share with you the chemical names for sugar – ready?  Sucrose, saccahrose, beta-D-Fructofuranosyl-alpha-D-glucopyranoside.  The formula for Sugar is C₁₂ H₂₂ O₁₁

Bubbles, bubbles, bubbles – welcome to today’s bubbly blog. Our subject today is ‘Bubbles’! Now, way back when you were a wee little one, you remember the fun you had with bubbles. Bubble gum; blow them bubbles and then “pop” - yuck – gum all over the face, pull it off, shove it back in the mouth and back to blowing more bubbles. How about the little bottle of bubble soap that you bought for a dollar at the dollar store. You pop the cap and then pull out the little wand, dip it in the soap mix and wave it about – then you have a parade of little bubbles floating about in the wind – try and grab one and it goes ‘pop’!

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