If oxygen has 6 valence electrons how many it would like to gain to have full valence shell? And what charge will it give to oxygen ion?

Gain 2, and become negatively charged

Explanation:

A full valence shell, thus stablilized, has 8 electrons, and so it would need two more, and when atoms gain electrons, they become negatively charged because there are now more electrons than protons (and so, when they lose electrons, they become positively charged). Hope this helps! :)

the answer is a

photosynthesis

wher is the rest of the question