Well oxygen has 6 electrons in its outer shell and mg has 2. Oxygen need two to complete it's outer shell and mg needs to lose 2 to gain a complete out we shell.
Answer:
Chemosynthesis is a process by which energy is derived via the microbial mediation of certain chemical reactions. The source of energy for chemosynthesis is energy liberated from a chemical reaction (the oxidation of an inorganic substance) rather than energy harvested from sunlight or other light.