Transcript WELCOME TO THE POWERPOINT PRESENTATION ON A …

ins p i re
INnovation in Science Pursuit for
Inspired REsearch
inspire
INnovation in Science Pursuit for Inspired REsearch
inspire – 2012 - 2013
Department of School Education,
O/o. District Educational Officer,
Sri Potti Sri Ramulu Nellore District.
A POWERPOINT
PRESENTATION ON
A SAMPLE WRITE UP
ON A CHEMISTRY THEME..!
: CHEMISTRY :
Make Your Own
Markers
Abstract :
Do you ever wonder how markers are
made? Where do all of those colors come
from? Many of the colorful dyes we use
come from plant pigments. Pigments are
what make the world around us so
colorful. How do chemists turn those
natural plant pigments into art supplies? In
this science project, become a chemist
and make your own marker out of a
drinking straw and homemade plant dye!
Objective :
In this science project, you will
extract plant pigment and use
paper
chromatography
to
compare the pigments to color
molecules
in
water-soluble
markers.
Introduction :
• Many modern products are made using bright colors. The many
colors come from colored molecules that are mixed into the material
used to make the product. There are many examples, including
food, plastics, art supplies, and fabric. Some colored molecules are
synthetic, like the famous Yellow #5, found in many candies and
food products. Others are made from natural pigments found in
plants.
• A pigment is a protein molecule from a plant that reflects a certain
color of light from the sun. This color is reflected and seen by your
eye, which tells your brain that you are seeing a certain color.
Sometimes plants contain many pigments that mix together, but your
eyes see the pigments as only one color.
• Oftentimes, the colors that we see in nature or in manufactured
products are mixtures of different-colored molecules. Even though
our eye sees the result as one color, each of the separate color
molecules stays true to its own color in the mixture. One way to see
this is to find a way to separate out the individual color molecules
from the mixture, to reveal their unique colors.
• Chromatography is the way chemists separate the
components of a mixture into individual molecules.
During chromatography, the components of a mixture
start out in the same place, but are separated by their
chemical properties. The type of paper chromatography
you will use separates pigment molecules based on
their size, because small molecules will move faster
through the paper than the larger molecules. Imagine
that you and your parents are running through a crowded
park. You will probably get to the other side faster
because you are smaller than your parents are.
• In this science project, you will learn how to extract
pigment molecules from plants, and compare them to
synthetic color molecules using paper chromatography.
Will the natural and synthetic dyes have the same or
different color components? Can you use your
homemade dye to make your own markers?
Terms, Concepts, and Questions to Start
Background Research :
• To do this science project, you should know what
the following terms mean. Have an adult help
you search the Internet or take you to your local
library to find out more :
•
•
•
•
Pigment
Chromatography
Molecule
Dye
Materials and Equipment :
• A colorful spice, tea, plant, fruit, or vegetable (good sources
should be rich in color and include, but are not limited to:
blueberries, cranberries, beets, yellow onion, red onion,
turmeric, black tea, coffee). Note: Be sure you have enough to
cover the bottom of a saucepan.
• Cutting board (if you need to chop your plant source into small
pieces)
• Knife (if you need to chop your plant source into small pieces)
• Saucepan
• Stove
• Water
• Bowl
• Strainer (if using a plant source that does not dissolve in the
water)
• Large glass jars (2), canning jars that are about 6 1/2-7 inches
tall work well.
Materials and Equipment :
• Lab filter paper (4 1-inch-wide strips that are 1-2 inches taller
than your glass jars; you will use 2, but need extra to allow for
mistakes); can be ordered from an online science supplier like
Carolina item #712802. Note: Coffee filter paper will not work.
For more information on which papers will and won't work,
see our Paper Chromatography Resources guide.
• Drinking straws (2)
• Ruler
• Dropper, such as an eye dropper
• Water-soluble marker to match your dye color
• Lab notebook
• Cotton cording, 1/2-inch diameter; found at a fabric or hobby
store
• Piece of string that is about 8 inches long
• Newspaper
• Small piece of clay
Experimental Procedure :
•
•
•
•
Pick out a plant source to extract your dye from. Make sure
you have enough of the plant source to cover the bottom of
a saucepan.
If your plant source is large, you will need to finely chop it
into little pieces using your knife and cutting board. Have an
adult help you with this step. If the color is concentrated into
the skin, you might want to peel the skin off and use only the
skin.
Add the plant material to your saucepan and add just
enough water to cover the plant source. If you selected tea
or a spice, add enough water so that it is floating or mixed
into the liquid and not just absorbing the water or turning into
a paste.
Bring the mixture to a boil and simmer covered on the stove
for approximately 10–15 minutes. The pigment from the
plant material will slowly begin to color the water in your
saucepan.
Figure :
Figure 1. The diagram
above shows how each
glass jar should be set
up. Make sure that each
dye you test is in its own
jar and that all dye spots
are 2 inches from the
bottom of the filter paper.
–
Safety Notes: Do not leave the plant-water mixture unattended
on the stove. Remain nearby to make sure it does not burn. It is
also a good idea to do this in a well-ventilated area, or with the
stove top fan running, in case the cooking plants release badsmelling fumes.
•
If the color of your water is too faint, you may want to concentrate the
color by removing the lid of the saucepan and continue boiling until
enough liquid has evaporated, leaving behind a darker liquid.
•
When the color of the water is rich in color, remove the saucepan
from the heat and allow the dye to cool. If there are pieces of material
in your saucepan, separate the dye into another bowl using a strainer
and set the bowl of dye aside. If your plant source dissolved, just
pour the liquid into a bowl and set it aside.
•
Now that you have your homemade dye, you will want to compare it
to a dye from a similar color of water-soluble marker.
•
Cut two strips of filter paper that are each 1 inch wide and 1-2 inches
taller than your glass jars.
•
Poke a hole in the top of each filter strip, and push a straw through
the hole.
•
Use the straws to hang your filter strips into the two glass jars, so that
just the bottom part of the filter strips touch the bottom of the jars. There
should be one strip in each jar. Trim the strips, if necessary.
•
Now remove your filter strips and pour about 1 inch of water into the
bottom of each jar. You can use your ruler to measure.
•
Using a dropper, at the bottom of your first filter strip, carefully squeeze
out a small drop of dye 2 inches from the bottom of the strip. The drop
size should be about the size of a pencil eraser. If your dropper puts out
a drop that is much bigger than that, you will need to repeat steps 8-12
with a new strip.
•
Allow the spot to dry. If after drying, the spot is too faint, you will need to
repeat steps 8-12 with a new strip to make your spot darker.
•
Now, using the water-soluble marker that is the same color as your dye,
take your second filter strip and make a dot the size of a pencil eraser
that is 2 inches from the bottom.
•
When the spots are dry on both strips, hang the strips in your
chromatography chamber glass jars. The level of the water should be
below the spots of color, and the spots of color should both be 2 inches
above the bottom of the jar. The setup for each glass jar should look
similar to the diagram in Figure above.
•
Now watch as the water moves up the filter strip. What happens?
•
When the water reaches the top of your strip and you can see that
the colors have separated, remove your strips from the jar and allow
the strips to dry.
•
Lay your strips side by side to compare the color components. Make
a drawing of each strip in your lab notebook. What do you notice?
Make a list of similarities and differences.
•
Now you are ready to make your dye into a marker. Cut a piece of
1/2-inch-diameter cotton cording that is 1/2 an inch longer than your
straw. Tie a piece of string to one end of the cotton cording to help
you pull it through the straw later.
•
Lay your piece of cording over the edge of the bowl of dye so that
only half of the piece is soaking in the dye. You should soak the end
that does not have the string attached to it. Soak the cording for 5
minutes.
•
Lay down some newspaper so you do not spill dye on your work
surface.
•
Now slowly and carefully thread the string through the straw and pull
your wet piece of cording through the drinking straw. Watch out, this
will be messy!
•
Plug the end of the straw with the string coming out with a small
piece of clay.
•
Let the cotton cording hang out of the other end of the straw, this will
be the end you will use to write with.
•
Now you are ready to write a message or draw a picture with your
new homemade marker!
Variations :
• Try other sources of material to get new and different
colors of dye. Can you try to make yourself a complete
set of homemade markers? Which materials made the
best colors?
• Another fun chromatography project is to use Kool-Aid®
as a source of pigment. Conduct an experiment using
your favorite flavors of Kool-Aid. Do some of the different
flavors use some of the same coloring agents? Which
flavors contain mixtures of different colors?
• Some plant pigments change color when they are mixed
with an acid (like vinegar) or a base (like baking soda).
Conduct an experiment on different plant dyes to see
which ones have this amazing color-changing ability!
Bibliography :
• This web site at Chemistry 4 Kids has a great tutorial on
chemistry, matter properties, and mixtures. Go check it
out:
Rader, Andrew. (2005). Rader's Chem4Kids. Retrieved
December 13, 2005 from
http://www.chem4kids.com/files/matter_intro.html
• Burch, Paula. (2005). All About Hand Dyeing: About
Natural Dyes. Retrieved December 13, 2005 from
http://www.pburch.net/dyeing/naturaldyes.shtml
• Cobb, Vikki. (1972). Science Experiments You Can Eat.
Harper Collins, New York, NY. Retrieved December 13,
2005 from
http://www.vickicobb.com/scienceyoueat.html