Sort the chemical equations based on the chemical reactions they represent. water → hydrogen + oxygen
iron + oxygen → iron oxide
sodium + chlorine →
sodium chloride
sulfur + oxygen →
sulfur dioxide
potassium + chlorine →
potassium chloride
calcium carbonate →
calcium oxide + carbon dioxide

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."

not sure if this is what you'r looking for eubacteria and archaebacteria

idk what the options are but

these is a strong electrostatic attraction between the ions hence a lot of energy is needed to overcome this attraction

this is why the boiling points are so high