Ammonia and oxygen react to form nitrogen monoxide and water 4NH3 (g) + 502 (g)-4NO (s) + 6H20 (0 How many moles of oxygen are present if the oxygen gas oc cupies a volume of 35.6 L at STP? A moles of oxygen What mass of ammonia (MM - 17.04 g/mol) is needed to completely react with the given quantity of oxygen? A grams of ammonia