The gas that living things need to survive is composed to two oxygen atoms covalently bonded to each other (O2). A- humans artificial bond molecules together so we don’t run out of useable oxygen. B- Oxygen does not have a full nucleus of protons, and therefore binds with other molecules to fill each of their nuclei. C- Oxygen is a very sticky element and therefore gets stuck to also other atom floats past. D- Oxygen does not have a full valence electron shell, and therefore binds with other molecules to fill each of their shells. HELPP PLS !

elements

explanation:

yes the other ones are right just show me a pic of ur face cuz u look hot

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-

if you're asking what comes out, it's steam.