## Nature’s Density

What is
Density? Density is how much ‘stuff’ is packed into a particular area.

For
example, if we have 13 balls in a box and we have the same box with 27
identical balls inside it. We say the box with 27 balls has higher density than
the box with 13 balls.

Density
is a fundamental property of matter. Density is defined as mass divided by unit
volume. It is measured in grams per cubic centimeter or kilograms per cubic
meter. The Greek letter rho, is the symbol for density.

Density,
ρ = Mass ÷ Volume

So,
two liquids can take up the same amount of space(volume) but can have
completely different masses. If liquid A has a higher mass, MORE of that liquid
is in that space and therefore is denser. If liquid B has a lower mass, LESS of
that liquid is in that same space and is therefore less dense than liquid A.

All
liquids in your tower have similar volumes but they have different densities.
What does that mean? That means that each liquid has a different amount of mass
in that volume. The liquids with the highest density are at the bottom, and the
ones with the lower density are on top of each other. So, which of the liquids
is most dense? And which is least dense?

## Bag Stab & Polymerization

A plastic bag is made of polymers, long chains of individual molecules called monomers. When a sharp pencil pierces the bag the polymer chains separate without breaking. The chains of molecules then squeeze tightly around the pencil creating a seal that prevents it from leaking.

Polymers
find use in our everyday life, from water bottles and Tupperware to tires for
automobiles. The word polymer
is derived from the Greek root poly-, meaning many, and mer, meaning part or
segment. Many of the same units (or mers) are connected together to form a long
chain or polymer.

Polymers
are of two types: Polymers such as starch, proteins and DNA occur in Nature,
and are called Natural polymers. Synthetic polymers are derived from petroleum
oil and made by scientists and engineers. Examples of synthetic polymers
include nylon and plastic.

Long
repeating chains can be linked together to form a cross-linked polymer, which
may become branched and become a Branched chain polymer. As the degree of cross
linking in the polymer increases, the polymer usually increases in rigidity and
toughness. This is why we see plastics that have different degrees of hardness
from a plastic bag to a hard-plastic baseball bat.

HTHT @ Home Science Experiment and learn about polymers:

## All Candy. All Science. All FUN – Make Your Halloween Scientifically Spooky!

Drop a Warhead in baking soda water, and bubbles erupt. Leave a Skittle in water, and the S floats to the surface. Melt a Starburst, and shiny oil spots form. That’s right, next week is Halloween which means – All Candy. All Science. All FUN!

Candy experiments are a great way to use up all of that candy & still enjoy all the sweetness Halloween has to offer.  Why not play with your candy? Any seasoned trick or treater knows that his loot is full of candy that brings lots of unwrapping and stirring and sticking things together – it’s one of the important parts of the trick or treating experience. We love candy experiments because they can teach basic science lessons about topics such as density, dissolving, and nutrition. Listed below are just a few ideas to get started. Have fun, and as always, let curiosity be your guide!

Here’s A Few of our Favorite!

Acid Test: This experiment tests for the acid often found in sour candy.

Chocolate Bloom: Chocolate is made of cocoa butter, cocoa solids, and other ingredients that have been mixed together. Can you take them apart?

Color Separation (Chromatography): You know candy is colored with artificial dye. To see the different dyes for yourself, try this.

Density Rainbow: Sugar water is denser than water—the more sugar, the denser. This experiment shows you how to layer different densities into a rainbow.

Dissolving Hot/Cold: See if candy dissolves faster in hot or cold water.

Hidden Candy: Most candy is made from sugar, corn syrup, and flavorings. These ingredients are used to sweeten lots of different foods. Can you find the “hidden candy” in other varieties of food you eat?

Lifesaver Lights: Do wintergreen Lifesavers really make a spark in the dark?

Sink/Float Most: candy sinks in water, because sugar is denser than water.  But some will float. Why?

Oil Test: If you thought your candy was all sugar, think again. Many chewy candies also contain oil. This experiment uses heat to let you see the oil for yourself.

Pop Rocks: What’s the secret ingredient in the candy that crackles?

Sticky You: know candy can cling to your fingers—but how sticky can you make it?

The fun doesn’t stop there! Check out these additional resources on ways to make your Halloween scientifically spooky!

## Celebrate Leap Day – The FUN Science of Telling Time!

Thirty days hath September…but why on earth does February have 29 every four years?

This year is a leap year, making the length of the 2012 calendar 366 days, instead of the normal 365.  Every four years an extra day is added to the month of February, but have you ever wondered why this happens?  In celebration of 2012 being a Leap Year, we invite you to hop back in time with us for a brief history of our modern day calendar and discover the FUN science of telling time!

The calendar is supposed to match the solar year, in other words, the length of time it takes for the Earth to orbit the Sun once. But things aren’t quite that simple. It actually takes Earth 365 days, 5 hours, 48 minutes and 46 seconds to complete its orbit (about 365 1/4 days). Those extra hours gradually add up so that after four years the calendar is out of step by about one day.  Adding a day every four years allows for the calendar to match up with the solar year again.

However, because the solar year isn’t exactly 365 days, even adding a leap day every four years means that the calendar is still out of step by 11 minutes and 14 seconds each year. Over the course of 400 years this would add up to three extra days. In order to solve this problem it was decided to leave out the leap year three times every 400 years. So the new rule was, a century year (1600, 1700, 1800, etc..) would only be a leap year if it was evenly divisible by 400.  This means that the year 2000 was a leap year, but 2100 will not be.

Phew! So, who figured all this out?

The Egyptians were the first people to think of adding a leap day to the calendar. Later, the Romans copied the idea and in 1582 Pope Gregory XIII reformed the Julian Calendar (introduced by Julius Caesar in 45 BCE). By Pope Gregory’s time, the calendar had drifted 14 days off track. He neatly solved this by wiping ten days off the calendar, telling everyone that the day after October 4th was going to be October 15th. Bad luck for people with birthdays during that time, including famous scientist Sir Isaac Newton. His birthday according to the Julian calendar, used during the year of his birth, was Christmas Day, 1642. However, once the Gregorian Calendar went into effect,Newton’s birthday changed to January 4th, 1643.

The early roman calendar originally began the year in the month of March. It consisted of ten months, each lasting about 30 days, ending with December. This ten month calendar completely left out the winter months.  It is thought that the two extra months, January & February, were added sometime around 715-673 BCE. This would have made February the last month of the year, which might explain why a leap day was added to that month. Later, it was decided to start the year with January.

Other nations have different leap year rules and different methods of keeping their calendar in line with the solar year.  Countries may have a day, or in some cases a month, that gets added every few years in order to balance the time. The Chinese, for example, add a month about every three years, whereas in the Islamic Hijri Calendar a day is added 11 times during a 30-year cycle.

It can be pretty confusing keeping track of our modern day calendar, but just remember…

Thirty days hath September,

April, June and November;

All the rest have thirty-one

Save February, she’s alone

Hath eight days and a score

Til leap year gives her one day more!

Did You Know?

There is a tradition that women are allowed to propose marriage to men on leap days! One day in the 5th century, St. Bridget complained to St. Patrick about the unfairness of the system which only allowed men to propose, so he decided to let women do the asking once every four years!  Today, we refer to this special day as Sadie Hawkins Day!

FUN BrainPOP Video about leap year

Leap Year 2012

Take The Leap: FUN Leap Year Quiz!

Happy Leap Day!

## Making & Recycling Paper At Home

Although thought of as an art, High Touch High Tech of South Florida uses this pulp recipe for paper-making science. You can use this activity not only to teach students how they can make their own recycled paper, but also teach students the value of recycling.

The following recipe & instructions come to us from High Touch High Tech of South Florida. Here’s how you do it!

To Get Started You’ll Need To Gather:

• Either a blender or hand blender
• Water source and measuring cup
• 2 –  Full Sheets of Newspaper- Shredded
• 1/2 – Cup of Flour
• 12 –  Sheets of Toilet Paper
• 2 –  Paper Towels
• 1 –  Gallon Size Ziploc Bag
• 1 –  Towel or felt to spread out wet paper for drying

Set up in an area where a wet mess will be easy to clean up. Probably outdoors would be best at first.

First, tear up & shred the newspaper into pieces. You will only need a couple sheets to get started, our recipe calls for 2 sheets of newspaper. If you are in the mood to mix it up a bit, you can use any type of papers with different textures, such as construction paper scraps, used computer paper, pages from old magazines etc. Colored paper is fun too! The more newspaper you use, the thicker and lumpier your resulting paper will be. We found construction paper gave us a fine, smooth paper that was flexible. Play around & find the mix you like best.

Add the shredded newspaper scraps into the blender, making sure you don’t over pack the blender.  Next, fill the blender with approximately four cups of water. First, turn the blender on & press the “puree” button for about 30 seconds.  This helps break down the paper quickly & helps eliminate clumps or large pieces.  Now you’re ready to blend on the “liquefy” setting for 1 1/2 to 2 minutes, until the paper is no longer recognizable and looks “pulpy”. Watch your blender carefully as you don’t want to burn out the motor.

Once the pulp is ready, it is time to press out the excess moisture. Place your cloth towel,  laying flat in the bottom of the sink.  Pour the pulp directly into your cloth towel. Using the towel, squeeze out the excess water. Hint: the more water you remove at this step, the less time it takes to dry!  With all the excess moisture gone from the pulp, you are almost finished!

If you don’t plan to use your pulp right away, seal it in an airtight bag and store it in the freezer. Simply thaw the pulp when you are ready to use it. This recipe makes 1 batch of pulp, enough for one class or 20 kids.  To make paper, place a small amount onto a piece of aluminum foil. Place a piece of wax paper over the top of the pulp and use a small rolling pin to flatten or shape your paper. Use markers or water color paints to decorate your paper. Additonal ideas include: pull off pieces of the pulp (about the size of a walnut) and let the kids press it into small molds or shape it free form and let it dry.  The thicker the form, the longer it will take to dry.

Warning:  never dispose of paper pulp down the drain.

High Touch High Tech of South Florida uses this pulp recipe to teach paper-making science. You can use this activity not only to teach students how they can make their own recycled paper, but also teach students the value of recycling.  If you think up and perform an experiment with recycled paper, be sure to let us know.