Most atoms do not. For those atoms that do not have a full valence shell (which usually would contain eight electrons, except for hydrogen and helium, where it would contain two), something has to change. So nature's tendency toward a full valence shell will lead to one of two things: The gain or loss of electrons.
A metal rail rusting in damp weather.
Okay for 8 it is the maximum levels will be higher and for 9 is poor circulation leads to lack of nutrients and oxygen
<h2>Input =

, water and Output =

</h2>
Explanation:
The light reactions of photosynthesis use water and produce Oxygen, NADPH.
The equation for photosynthesis :
→ 
The process of photosynthesis in two stages -
- The first stage is called the light reaction in which the light energy from the sun is captured and converted into chemical energy stored in the form of ATP and NADPH
- The second stage is the process of conversion of ATP molecules to sugar or glucose (the Calvin Cycle)
For a light reaction -
Net Input is of,
, 
Net Output is of, 
Raised temperature, decreased volume.
Temperature and Pressure are directly related, when volume increases so does the your pressure.
Volume and Pressure are indirectly related. When volume decreases, your pressure will increase.