For hundreds of years humans have been adding chemicals and other pollutants to the earths water supply. Can earths water ever be clean and pure again? What is clean and pure water?

Pure water is a colorless, odorless liquid with no molecules

except H₂O in it. You can buy it at the supermarket, or make

it at home if you have the equipment and know how to use it.

At the supermarket, it's sold in gallon jugs, marked "Distilled

Water".

It turns out that pure water tastes bleah, and you would not

want to drink it for very long.

The Earth's water cycle is constantly purifying our water.

When the sun warms the ocean's surface and evaporates

water, what evaporates and rises into the atmosphere is

pure water. The pollutants don't evaporate. The clouds,

the rain, and the rivers are self-purifying. Another example

of a process of nature that makes life possible here.

The junk is collecting in the oceans. We're lucky that the oceans

have such huge volume that we haven't been able to significantly

pollute that entire layer of the Earth and kill off all sea life yet.

But we're working on it.