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Syrup is Thicker than water

3/26/2015

Hooray for snow! Wait, you’re thinking. Why is she cheering on the lingering winter? If you remember from my last post, the warmer weather meant an early demise for the maple syrup season. The presence of snow means that the night time temperatures are dropping below freezing! If day time temperatures also rise above freezing, then the maple sap will continue to flow out of maple trees that are tapped!

If any of you attempted to make syrup following the recipe we posted, I’m sure you noticed something as your concoction boiled. The water evaporated, leaving the sticky, sweet and thick syrup. This syrup that remained was much, much thicker than the liquid that you started with. The thickness of syrup can be measured by density. Density is a measure of how tightly packed the molecules are in a substance.

Feathers and Bricks

Have you ever been asked this trick question: “Which weighs more – a pound of feathers, or a pound of bricks?” The answer, if you think for a moment, is that they both weigh the same! One pound of anything weighs . . . well . . . a pound! So, the fact that you are comparing feathers and bricks does not make a pound of either of those things weigh more or less than the other.

We could pose the question a little differently in regards to density though. Which is more dense, a pound of feathers, or a pound of bricks? The answer would almost certainly be that the pound of bricks is denser. One brick probably weighs a pound. (Picture a brick the size of your shoe). How many feathers would equal a pound? (I’m picturing something like a pillowcase stuffed with feathers). Of those two pictures, which is denser? The bricks, of course! If you took a fistful of feathers the same size as a brick, they would have far less matter than the brick does.

Now, think back to the syrup and water. If you have one cup of syrup and one cup of water, which one is most dense? If you guessed the syrup, you guessed right! There is more matter in the cup of syrup than in the cup of water.

Liquid densities are really interesting to explore. A liquid that is less dense than another liquid will float on top of it! If you pour a glass of water on syrup, the water will float on top of the syrup.

To test your knowledge of liquid densities, try out this experiment below. You’ll feel like a scientist and a magician as you stack liquids on top of one another.

Layers of Liquids - Exploring Density

WHAT YOU'LL NEED:

Containers -

A tall glass cylinder to hold your liquids. Ideally, it will be like a graduated cylinder that chemists use, but if you have a tall, narrow glass vase that should work as well.
Cups for each liquid ( 9 oz. each)

Liquids –

Honey
Light Corn Syrup
Dish Soap
Milk
Water
Lamp Oil
Vegetable Oil
Rubbing Alcohol

Optional Household Objects –

Food-coloring (to color your non-colored liquids)
Ping pong ball
Plastic cap from water, soda, or milk bottle
Plastic craft bead
Cherry tomato
Dice from board game
Popcorn kernel
Metal nut or bolt

EXPERIMENTAL PROCEDURE:

1. What you will be doing is gradually adding each liquid on top of the others, starting with the densest at the bottom. Pour 8 oz. of each liquid into a separate cup (if you have clear cups, they work best for observation).You should have 8 cups. If you would like to add color to any of the clear liquids, now is the time to use of your food coloring. Try using all different colors, so you can clearly see the differences in your column.

2. Prior to reading the order of densities, sit down and look at all your liquids and write down the density order that you think will describe the column. If you are doing this with young children, have them draw a picture of what they think the column will look like.

3. Now that you have made what we scientists call a hypothesis, you can read the correct order. Slowly, begin by pouring the honey into your cylinder. You should pour in such a way that the liquid travels down the middle of the cylinder WITHOUT touching any of the sides of the cylinder. Continue pouring each liquid in this manner. You will be pouring the light corn syrup next.

TOP OF CONTAINER
LAMP OIL
RUBBING ALCOHOL
VEGETABLE OIL
WATER
DISH SOAP
MILK
PURE MAPLE SYRUP
LIGHT CORN SYRUP
HONEY
BOTTOM OF CONTAINER

4. The liquids may look like they are combining, but if you wait a few minutes, they will settle into a column based on the order in which you poured them into the container. Why is this happening? How are the molecules in the honey at the bottom different than the molecules in the lamp oil at the top?

5. Have your children draw a new picture of the density column with the correct order of liquids. The first was their original hypothesis. Now, they can compare their hypothesis with what the outcome actually looked like.

6. Continue experimenting with your density column by dropping small household objects into it. Your goal here is to determine the approximate density of each object in relation to your liquids. Before dropping each object into the column, guess where it will settle. For example, if you choose to drop in a bobby pin, you might guess that it will rest on the layer between the maple syrup and the milk. If this is your hypothesis, then you are saying that you think the bobby pin is more dense than milk but less dense than the maple syrup. Using the second drawing, you can continue adding elements to your density column drawing!

WHAT'S HAPPENING?

You are using the exact same volume of each liquid, but these liquids have different masses. Liquids with greater mass (higher density) have more molecules packed into the same amount of space than those with smaller amounts of mass (lower density)!

Inspiration for this Experiment was from:
http://www.stevespanglerscience.com/lab/experiments/density-tower-magic-with-science

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A Sticky Situation

3/19/2015

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Warm Spring

A warmer than usual spring has led many of us to tuck away our winter coats in favor of lighter jackets and wind breakers. Those of us who are particularly cold-hardy are already braving the streets in shorts! It’s only mid-march, yet we have had unseasonably warm temperatures so far.

While this warmer weather makes most of us jump with joy, did you know that there may be less maple syrup this year as a result? You’re probably wondering how the warm weather has anything to do with syrup that you put on your stack of pancakes.

the story of our syrup

Where does syrup come from . . . besides the grocery store? While we do buy our syrup in bottles at the grocery store, many of these bottles list corn syrup as the number one ingredient followed by a dozen or so extra ingredients. Pick up a bottle of real maple syrup and only one ingredient is listed: maple syrup. This is the good stuff that we get from the sap of maple trees.

No, the Keebler cookie elves that live in trees have not expanded their inventory. You don’t just press a button and out pops the syrup. It’s actually quite a process to get the sap out of the tree and to turn it into syrup. Before we talk about how to make syrup, we first need to understand how the inside of a tree works.

Trees have living vascular tissue beneath their bark. Xylem tissue is made of thick tube-like cells that transport water and minerals from the roots all the way up to the leaves. Xylem tissue replaces itself every year. The old cells dies and are replaced by new cells. This is why we see growth rings in a cross-section of a tree that has been cut down. Phloem tissue is made of thinner cells that carry glucose (sugars made from photosynthesis) throughout the tree wherever it is needed.

The tree stores extra sugars in its vascular tissue over the winter. In the spring, these excess sugars become accessible in the sap for us to tap. To tap a maple tree, a small funnel instrument called a spile is placed into a hole drilled into the vascular tissue. A bag or bucket is then attached to the spile to collect the sap as it slowly drips out of the tree.

Less Syrup this spring

So, why is our unseasonably warm spring affecting sap flow? The sap is freed from the cells of a tree’s vascular tissue when night time temperatures fall below freezing and day time temperatures rise above freezing. Typically, our weather in Minnesota allows for sap to flow throughout most of the month of March. At Lowry Nature Center in Carver Park, about 200 gallons of sap were collected last year. So far this year, only 30 gallons have been collected. If we have a drop in night time temperatures, the sap may yet continue to flow for a couple more weeks. However, it is interesting to observe how seasonal temperature differences can affect something like the amount of syrup we have for pancakes!

Click for News Story about Syrup this Spring

Sap to Syrup

Once sap has been collected, is it ready to use? Sap direct from the tree does contain sugars, but it wouldn’t be very tasty to pour it directly onto your pancakes. You would get very soggy pancakes because sap is made mostly of water. To make syrup from the sap, you need about 40 gallons of sap for every gallon of syrup. To get syrup, the sap is boiled down until most of the water has evaporated. Then, the sticky stuff remaining is filtered through wool felt or cheesecloth to remove any impurities. Finally, the syrup is ready to put in jars for use!

Make your own maple syrup

If you have sugar maple trees in your yard, consider tapping them to make your own authentic maple syrup! Follow this MN DNR link to learn how to get started:

MN DNR Link

If you don’t have maple trees available to you, consider going to an event at a nature center to learn more about the maple syrup process. Many free events are offered through Three Rivers Park District each spring.

If you and your kids would like to observe how sap turns to syrup at home, try the following recipe at home:

What You’ll Need:

8 cups granulated sugar
1 cup packed light or dark brown sugar
1/2 cup honey
4 cups water
2 teaspoons pure maple extract
2 teaspoons pure vanilla extra
Mason Jars or other glass containers to store syrup (Makes about 2 ½ quarts)
A large 5-6 quart pot

What to Do:

1. On the stove top in your large pot, combine the sugars, honey, and water. Gently stir the mixture so that the sugars begin to dissolve. Bring the mixture to a boil. Then, reduce the heat and allow to simmer for 15 minutes.

2. Remove from heat and allow it to cool for 20 minutes. Add the maple and vanilla extracts and stir.

3. Cool for another 40 minutes or so, stirring occasionally. When cooled to room temperature, fill your jars!

This syrup will stay fresh in the fridge for about 2 months. Share with your friends and neighbors and tell them all about how maple syrup is made . . . from tree to table!

While You’re Cooking:

Think about what is happening to your sugar/water mixture as it is cooking. Why does it change in appearance as you heat it up?

The sugars dissolve into the water. As the water heats up, the water molecules begin to move more quickly. At the boiling point of water (212 degrees Fahrenheit), the water changes phases, turning from liquid to gas as it evaporates.
As more water evaporates, you are left with thick, sugary syrup. This process is exactly the same in real maple syrup production!

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Spring Showers

3/12/2015

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Do you have a little spring in your step this week because of the beautiful weather change? I know I do! If you compare winter with spring, can you think of several differences between the two? In Minnesota, the weather seems to drastically change from one week to the next with the change of seasons. One week you go outside needing your winter coat, a hat, mittens, and three scarves. The next week you go out with all your gear ready to face the day, and it’s a balmy 50 degrees outside! Here are a few weather differences in winter and spring that I came up with. Did you think of any others?

WINTER

Colder temperatures
Less direct sunlight (You can stand in the sun, but it does not feel quite as warm as it does in summer.)
Precipitation comes in the form of snow

SPRING

Warmer temperatures
More direct sunlight (When you stand in the sunlight, it is beginning to feel warm.)
Precipitation comes in the form of rain

In the springtime, the sun is beginning to appear higher in our sky, so the temperatures are warming up. When the temperatures warm, a very interesting thing happens to the moisture in our air. Instead of falling to the ground in frozen flakes, it falls in drops of rain! We love to get rain in the spring because it waters the earth and helps all of our plants begin to grow again, not to mention it also makes puddles that are awfully fun to splash in.

There are always tiny drops of water in the air called water vapor. Warm air holds more water vapor than cold air holds. Warm air likes to rise up, and it takes the water vapor with it. When this water vapor is exposed to air, it condenses around tiny dust particles in the air to from droplets. All these tiny droplets collect together in the form of clouds. When a cloud gets very heavy with water vapor, gravity begins to pull some of them down to earth again – in the form of rain.

As I look outside this morning, the sky looks like it might be threatening to rain later today or tomorrow. While you are waiting for it to rain outside, you can make your own rain cloud at home inside!. Just follow the directions below:

MAking it rain indoors

WHAT YOU'LL NEED:

A clear glass container to hold your cloud (a circular container such as a fish bowl would work best, but you could also use a large mason jar)
A can of inexpensive shaving cream (check out the dollar store)
An extra glass to hold your water vapor mixture
Blue food coloring
An eye dropper or turkey baster
Water

WHAT TO DO:

1. Fill your clear container ½ or ¾ full of water.

2. Squirt your shaving cream cloud on top of this water. Feel free to make a big cloud!

3. Mix blue food coloring with water in your second glass. Use a lot of food coloring to make sure you’ll be able to see the rain as it falls.

4. Take your eye dropper or turkey baster and slowly squirt your water vapor mixture into the cloud.

5. Try to guess how much water vapor the cloud will hold before it gets too heavy and rain begins to fall!

It's not every day that you see a rain cloud inside your house!

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It's a solid? It's a liquid? It's a non-Newtonian Fluid!

3/5/2015

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Imagine yourself walking through a remote jungle on an expedition to find an exotic bird species. In your excitement to see this bird, your eyes never leave the canopy of trees above you. With binoculars pointed up at the treetops, you continue walking forward only to realize after a few paces that your hiking boots will not budge. You’re stuck in something. You pull your legs up as hard as you can, but to your dismay it does not help. Not only are you stuck . . . but you now realize that you are also slowly sinking down into the muck. You suddenly realize what you are stuck in . . . quicksand!

Living in Minnesota, we have all probably walked along the sandy beach of one of our state’s 10,000+ lakes. More importantly, we have all walked along one or more of these sandy beaches without sinking down into them. So, what makes some sand “quick”? Quicksand is formed when a solid like sand or silt combines with clay and large amounts of water. The sand is so saturated with water that sudden changes in pressure (i.e. an earthquake or someone walking on top of it) will cause the liquefied soil to lose strength and collapse.

Quicksand is what scientists call a non-Newtonian fluid. If you look at it, it appears to be a solid. However, if something disturbs it and pressure is placed on it even slightly, then its viscosity will suddenly decrease. The viscosity of something is a measure of its resistance to stress. If you try to poke your finger through water in a glass, your finger will sink quickly to the bottom without much effort. Water has low viscosity. If you try to poke your finger through a glass full of honey, you’ll have a more difficult time reaching the bottom because honey has a higher viscosity. When an animal or human walks on top of quicksand, the added pressure lowers the viscosity, causing the quicksand to become more fluid so that you sink into it.

Despite what we see on TV or read in books, quicksand will rarely swallow you whole. It would be highly unlikely for your whole body to sink down into it. Back in the 1960’s, quicksand was so popular in media that 3% of all movies produced had a scene where someone sank into it! It is difficult to get out of quicksand because the added pressure of your movement displaces the water from the sand, trapping you in dryer sand. In order to move through that sand, you must apply a very large force to make room for water to flow back and allow more movement. The reason quicksand can be dangerous is not because it will swallow you up but because it can impair your movement and leave you exposed for long periods of time to the elements. If you ever do find yourself wandering through the jungle or any area where quicksand is common, make sure to watch the ground, not just the treetops, and always bring a buddy along.

We may not commonly experience quicksand here in Minnesota, but at Science Explorers, we often explore other non-Newtonian fluids in our classes. Remember, non-Newtonian fluids are substances that appear to be either a solid or liquid but when pressure is applied to them they change to the opposite phase. Most phase changes (i.e. solid to liquid, liquid to solid, liquid to gas), occur as a result of change in temperature. Non-Newtonian fluids are unique because they change phases quickly as a result of change in pressure.

Growing up, I loved to read Dr. Seuss books. (If I’m honest . . . I still do!). In Seuss’ book, Bartholomew and the Oobleck, the king of Didd decides he is tired of normal weather. He asks his magicians to create a new and exciting type of weather. The next day, the kingdom is plagued with an ooey, gooey, sticky green mess that never ends . . . oobleck.

This oobleck is another type of non-Newtonian fluid. To explore with it at home, follow our recipe and guidelines below!

Make your Own Non-Newtonian Fluid – OOBLECK

Supplies:

Mixing bowl

Mixing spoon

1 cup of water

1 ½ to 2 cups of corn starch

Food coloring (optional)

Before You Start:

If you would like, check out Bartholomew and the Oobleck by Dr. Seuss, from your local library and read before you begin.
Roll up your long-sleeves and prepare a spot on the kitchen counter or table where you have enough room to make a mess (without getting other things messy).

Making Your Oobleck:

1. Pour your water into the mixing bowl. If you would like to make your oobleck colorful (or green like in the story!), you can add food coloring to the water at this point.

2. Slowly add 1 ½ cups of corn starch and stir with the spoon. As you stir, the mixture will begin to thicken. You will need to switch to mixing with your hands.

3. Keep adding additional corn starch as needed. If you quickly poke the oobleck with one finger, and your finger doesn’t immediately sink into it, then the oobleck is at a good consistency. If it gets too thick, you can always add more water.

Exploring with Your Oobleck:

Oobleck is non-toxic. It is made with ingredients that are in foods you eat. However, be careful as you explore, and always wash your hands and your area of exploration after you are done.

While the is still in the bowl, take one finger and quickly poke the oobleck. What happens? Now, take your finger and slowly swirl it around in the oobleck. Does it react any differently?

Take a clump of oobleck and roll it into a ball. Let the ball rest on your outstretched palm or on the tabletop. Does it continue to behave as a solid after you have stopped rolling it?

For even more fun, take a large plastic bin and make a giant batch of oobleck. Take off your shoes and socks and try walking through the oobleck. Can you walk on top of it without sinking? Can you wiggle your toes in it?

The Science behind Your Oobleck:

The oobleck is a non-Newtonian fluid, just like quicksand. It changes quickly from liquid to solid based on how much pressure you apply.

When you quickly poked the oobleck, the corn starch suspended in the water resisted movement (higher viscosity). However, when you slowly swirled your finger through the oobleck, you gave the corn starch particles more time to move out of the way, so the viscosity did not change as much. Quick, high pressure makes oobleck appear more solid than liquid. Slow, low pressure makes oobleck appear more liquid than solid.

Cleaning Up:

You have now experienced the properties of quicksand without having left your home!

To avoid any younger siblings or pets getting stuck in your oobleck experiments, please make sure to clean up after yourself.

Make sure you mix any remaining oobleck in you bowl with plenty of water before dumping it down the drain.

Wipe up any dried out oobleck off surface with a dry towel. Then, take a damp towel or sponge to get anything that remains.

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Syrup is Thicker than water

Feathers and Bricks

Layers of Liquids - Exploring Density

A Sticky Situation

Warm Spring

the story of our syrup

Less Syrup this spring

Sap to Syrup

Make your own maple syrup

Spring Showers

MAking it rain indoors

It's a solid? It's a liquid? It's a non-Newtonian Fluid!

Make your Own Non-Newtonian Fluid – OOBLECK

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Syrup is Thicker than water

Feathers and Bricks

Layers of Liquids - Exploring Density

A Sticky Situation﻿

Warm Spring

the story of our syrup

Less Syrup this spring

Sap to Syrup

Make your own maple syrup

Spring Showers

MAking it rain indoors

It's a solid? It's a liquid? It's a non-Newtonian Fluid!

Make your Own Non-Newtonian Fluid – OOBLECK

Author

Archives

Categories

Our Services

Company

Staff Members

A Sticky Situation