How did chemisty and oceans produce this?

There is still a problem:

• Not much is available for anerobic processes to use.
• But hey, there is all this that we are floating in so let's do this

  

So, chlorophyll evolves to more complex forms so that it can capture and store enough UV energy to breaking the hydrogen-oxygen bond in water.

Now we have a mechanism to deliver Oxygen to the atmosphere via the aerobic photosynthesis of blue-green algae. But, the oxygen does not initially go into the earth's atmosphere:

So we have to do all of this before we have oxygen in the atmosphere as well as an ozone layer:

So now we can crawl out on the Land!