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We are a drama club and want to do a skit about being silent, when you see something done wrong. We want the actors to have blood on their hands (representing "if you're silent, the blood of that person who is being mistreated is on your hands). So the fake blood is made of corn syrup and food color. We want before our audience, to put the blooded hands into a clear glass bowl that is filled with water. When the actor brings his hand out of the water, we want his hands to be clean with no blood and the water to still be clear with no red residue. We would need to put something in the water that would not damager the actor's skin or hands, but would give us the result of a clean hand and clear water. DO YOU KNOW WHAT WE COULD PUT IN THE WATER SO THAT THE WATER WOULD STAY CLEAR AND THE HAND WOULD BE CLEAN?? Thank you so MUCH for your prompt responds to this question. We have to perform it on August 20th.
Question Date: 2011-08-17
Answer 1:

In order to have the blood go from red to clear, the dye needs to change chemically. I don't know exactly what dye you are using but my guess is anything that will make it go colorless should probably not be put on your hands. Instead, you may be able to use a different chemical as your dye such as an indicator like phenolphtalein. Phenolphthalein changes from red to clea, when the pH (aciditiy) changes from >9.8 to <8.2. This means you could add a little base (perhaps baking soda (Sodium bicarbonate) would work, soap, NaOH, or maybe a little ammonia) to the blood to keep it red and then add acid (lemon juice would work) to the water bowl. My biggest concern would be that phenolphtalein would be too "violet" and not red enough.

This is a similar idea...
click here

I'll keep thinking to see if I can come up with a better method.


Answer 2:

I want to state up front that I am not 100% sure this will work, but it should be very easy to try. If you add bleach to the water in the bowl beforehand, it might be able to make the water clear after adding the "blood". The way this works is that bleach oxidizes the molecules in the food coloring, changing them into different molecules that no longer reflect that color. In order to do this, you have to add enough bleach to oxidize all the food coloring that is going in. Bleach is very safe for the skin, with the following two warnings:

1.) Make sure the person touching the bleach washes their hand well before touching their eyes.

2.) If you touch anything else with bleach on your hands, for example, your clothing, you might take the color out of that material as well.

When I looked on the internet to see if this idea might work, I also read that adding baking soda to the bleach in the water helps the color go away even faster. Again, I'm not sure if it is true, but very easy to try. Baking soda is also very inexpensive and very safe.

Good luck!


Answer 3:

I think you might be able to do that more convincingly as a magic trick than as a science trick. I'm guessing you could have a trick container from a magic catalog that would let you show the audience either bloody water or clear water. Or you could have a table cloth on the table, and you would be sitting behind the table removing all the 'blood' with wet wipes before you put your hands into the water and it stayed clear.

Phenolphthalein is a pH indicator that makes the illusion of turning water into wine, because it is colorless and then reddish in acid vs base - or base vs acid. But I don't think it would do anything to eliminate the red of food color.

Best wishes,

Answer 4:

1. What Dexter didn't mention about his home made blood recipe is that red food coloring will stain your skin, so even if we can neutralize the color in the water you actors hands will still be pink. We can get around this with a different blood recipe.

2. I might not go a chemical route at all and rely on an optical illusion instead. I you have a large enough glass bowl you can tape in a plastic film across the bowl and then fill both sides with water at the same time. From the front of the bowl it should look unaltered but the film will act like a mirror and block the red water from being seen when they wash up in the bowl.

If this does not work you could play with making the blood with food color and oil. The oil will not mix with the water and will float on the surface but should wash off the hands the way you want it to.

Break a leg.


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