ChromophresGetting the color out

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Red eyes2

Have you ever seen advertisements for products to help a

person to get the red out of their eyes?

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A person’s eyes look red, so they put drops in their eyes. The drops begin to work to make the

blood vessels in their eye contract. The white part of the eyes appears brighter as the redness fades. (However, as the drops begin to wear off,

the redness not only returns—it can even become worse.)

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Can you remove the color from a Coca-Cola

so that it will become clear?

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For the first part of our demonstration we will pour some cola into a beaker and then add a

small amount of our mystery “invisible” solution.

As we stir the two together, what do you think will happen?

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Now let’s take plan water and add a few drops of food coloring. Now let us add some of our

mystery “invisible” solution to the colored water. What happened?

Can you guess what is the mystery “invisible” solution?

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That’s right! Bleach.

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To know what is going on it’s helpful to understand a bit

about how colors work. Chemical compounds — called

chromophores — cause colors by reflecting a certain

portion of the visible spectrum of light. For example, a green shirt contains chromophores

that reflect green light that our eyes see as the color green.

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What would you use if you wanted to remove the color from a piece of clothing?

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That’s right! Bleach.

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There are actually several different types of bleach. The most popular is common household chlorine bleach, which is a water-based product

that contains a chemical called sodium hypochlorite (NaClO).

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Another popular type of bleach is oxygen bleach, which contains hydrogen peroxide or other

compounds that release peroxide when mixed with water. Bleach also comes as a powder in the form of a

chemical called calcium hypochlorite.All of these bleaches can be used to whiten clothing. They are also used as cleaning agents, since they kill mold, germs, and bacteria. A solution of bleach and

water is often used to clean and disinfect hard surfaces in kitchens and bathrooms.

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How Does it Work?Bleach works by releasing oxygen molecules in a process called oxidation. The oxygen molecules released by bleach break up the chemical bonds

of chromophores.

The changed chromophore molecules either reflect no color or a color outside the visible

spectrum. This absence of color is seen by our eyes as white.

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You may have also noticed that fabrics left out in the sun will look faded or bleached over time.

Does sunlight have bleach in it? No! But sunlight can work like bleach. High energy ultraviolet

sunlight can disrupt the chemical bonds in chromophores, causing them to lose their color

much like the oxidation process with bleach.

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The Bible says that we are polluted or colored because of sin.

“Come now, and let us reason together, saith the Lord: Though your sins be as scarlet, they shall be as white as snow; Though they be red like crimson, they shall be as wool.” (Isaiah 1:18)

As nouns the difference between scarlet and crimson is that scarlet is a bright red, slightly orange color while crimson is a deep, slightly bluish red.

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Some artists believe that red and white produce the most

contrast. Fitting that God uses these two colors representing

pollution and purity to illustrate his ability to

cleanse mankind.

In our demonstration we used a substance that was already clear to remove the color from

another solution.

But God offers to use the blood of Jesus to remove the color of our sins and make us pure

represented by the whiteness of snow or the whiteness of clean lambs wool.

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As you may realize, snow actually has no color but the way light reflects off of it, it

has the appearance of whiteness. The purest white we can produce.

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But if we walk in the light, as he is in the light, we have fellowship one with another, and the

blood of Jesus Christ his Son cleanseth us from all sin. (1 John 1:7)

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And from Jesus Christ, who is the faithful witness, and the first begotten of the dead, and the prince of the kings of the earth. Unto him

that loved us, and washed us from our sins in his own blood. (Revelation 1:5)

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