Answer:
Explanation:
You just have to see the REACTANTS and PRODUCTS and look how much molecules are there and accordingly put numbers.
Eg:4Fe+3O2--------->2Fe2O3
Answer: B
Nitrifying bacterium, plural Nitrifying Bacteria, any of a small group of aerobic bacteria (family Nitrobacteraceae) that use inorganic chemicals as an energy source.
I'd say that the answer is erosion
You can calculate the gram formula mass of this compound by adding the atomic mass of every element in this compound according to the periodic table of elements.