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For Halloween, use the mixture to paint a pumpkin on a sheet of paper.   Have 
a plastic knife sitting in a glass of ammonia.   Cover the glass with foil 
and stick the knife through, to control the smell.   Tell the story of getting a 
pumpkin from a haunted pumpkin patch.   Then pick up the plasic knife and 
"slice" it across the pumpkin.   The ammonia turns the turmeric blood red, and as 
it runs down, it looks like the pumpkin is bleeding.

This Week's Experiment - Making Turmeric Paper 

Anyone that has ever taken a chemistry class or played with a chemistry set 
is familiar with litmus paper.   These little strips of paper change color to 
indicate whether a chemical is acid or alkaline (a base.)   There are other 
substances that also change color in the same way.

For this experiment you will need:

the spice Turmeric.   This yellow spice can be found in at your local 
grocery.
isopropyl alcohol, commonly known as rubbing alcohol.
a disposable plastic cup
a disposable paper or plastic plate
coffee filters
a variety of items from your kitchen.   Caution: Household cleaners can be 
toxic!   Be careful!!

Pour about half a cup of alcohol into the plastic cup.   Use a disposable 
cup, as the turmeric will stain it yellow.   Put about a teaspoon of   turmeric 
into the alcohol and stir.   Be careful not to get this on your skin or 
clothes, as it will stain them yellow.   Let it stand for about 5 minutes.

Cut several coffee filters into strips about an inch wide and three inches 
long.   Carefully dip each strip into the turmeric mixture and then place them 
on the disposable plate.   Let them dry.   They will be bright yellow.   It is 
ok if the part that you are holding does not get have the liquid on it.   The 
liquid is not harmful to your skin, but it will make you yellow for a day or 
so.   

Once the paper strips are dry, you are ready to test some substances.   Spray 
a little window cleaner onto one of the strips.   It will turn bright red, 
indication that it is alkaline.   Don't worry if several of the strips get 
sprayed and turn red.   In fact, it would be a good idea to spray several of them.  
 Again, let them dry.   

Pour a little vinegar into a cup and dip one of the yellow strips into it.   
Nothing happens.   Now dip one of the red strips.   It will turn yellow again, 
indicating an acid.   You can test all sorts of foods, to see which ones are 
acidic and which ones are alkaline or basic.   The same strip of paper can 
change color back and forth many times.

A dramatic variation of this is to bring a piece of yellow turmeric paper 
near the top of an open bottle of ammonia.   The fumes from ammonia are so strong 
that they change the paper red without any liquid touching the paper.   This 
is a very impressive demonstration.

You can make similar test papers with the juice from red cabbage, blue 
berries, black berries and other fruits.   Some work better than others.   It would 
make an interesting science project to see which fruit papers gave the most 
dramatic changes.

From Robert Krampf's Science Education Company
www.krampf.com

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