Plants give off oxygen as part of photosynthesis. Explain the impact of this process on humans?

This is a characteristic of the elements in the periodic table that shows a pattern. it may increase or decrease across or down the table.

In the 1800s, one of the statements in john dalton's atomic theory was that atoms are indivisible. later experimental evidence led to the discovery of subatomic particles such as neutrons, electrons, and protons. what happened to the indivisible atom part of dalton's atomic theory, and why?

What are the first three quantum numbers for the electrons located in subshell 2s?