Q: Why is the water blue?

Water; in terms of chemistry, H2O. We drink it, we swim in it, we bathe in it...those are just some of the common uses for water. However, why is the water blue? More importantly, is water really even blue? There are several theories for such. Let's explore deeper.

Sunlight is made up of all the colors of the rainbow: red, orange, yellow, green, blue, and violet. Some of the sunlight reflects off the surface of the water, in result, also reflecting the color of the sky. However then, why is the sky blue? The gas molecules in the atmosphere interacts with the sunlight before the light reaches to our eyes. The molecules scatter the higher-energy blue portion more than they scatter the red portion.

Back on the subject, however, water does not always appear blue. Compare the color of water in a bottle to water on the beach. Most likely, the water in the bottle looks clear, whereas the water in the ocean looks blue. Water can be different colors other than blue, from a greenish color...to even red! The colors that we see depend on the reflection of the visible wavelengths of light to our eyes. On the other hand, most of the ocean is completely dark. Hardly any light is able to penetrate deeper than 200 meters, and no light, whatsoever, will penetrate deeper than 2,000 meters.

So, the short answer? Water is NOT blue, but simply, a clear, colorless substance.

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