Alight-year is the distance light travels in

I believe that is space i would check just to make sure tho

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.

the dissolution of polymer can be thermodynamically described in 2 steps.