The by-product of photosythysis is

The by-product of photosynthesis is oxygen.

Explanation: The photosynthesis process is the process by which photoautotrophs convert light energy into chemical energy which can later be used to fuel the activities of organisms. The three important elements required for the photosynthesis process are Water, carbon dioxide and light. The product formed from this process, stored in the form of sugars, which are created from water and carbon dioxide. The by-product of the photosynthesis process is oxygen.

6CO2 + 6H2O → C6H12O6 + 6O2

Oxygen

Explanation:

Plants don't have any use for oxygen and we get oxygen from plants

more infor would

a lot

the seeing the electronic configuration we can say that the element is fluorine.

fluorine is the most electronegative element in the periodic table.

but by only seeing the configuration we cannot say about its reactivity because we don't know if its configuration after excitation or by addition of electrons.

but if not then, it is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. as the most electronegative element, it is extremely reactive: almost all other elements, including some noble gases, form compounds with fluorine.