Question

Hey guyzz..!! How are you all?? Here is my question.. :)
WHY..??vv
i) Mendeleev could not assign a correct position of hydrogen in his periodic table, as the properties of hydrogen resembles both with alkali metals as well as with halogens.

Answer 1

It is so because hydrogen has 1 valence electron in its outermost shell.so according to modern periodic table, hydrogen can be arranged in halogen family i.e. group no. 17 but hydrogen does not possess the properties of halogen family. That's why hydrogen is given its position in the first group and first period of the modern periodic table. that's why mendeleev could not assign a correct position of hydrogen in periodic table

Answer 2

Explanation:

Photosynthesis is a process used by plants and other organisms to convert light energy into chemical energy that, through cellular respiration, can later be released to fuel the organism's metabolic activities.