Question 1: when 0.2250 g of magnesium is heated with 0.5331 g of nitrogen in a closed container, the magnesium is completely converted to 0.3114 g of magnesium nitride. what mass of unreacted nitrogen must remain? question 2: a compound of uranium and fluorine is used to generate uranium for nuclear power plants. the gas can be decomposed to yield 2.09 parts by mass of uranium for every 1 part by mass of fluorine. if the relative mass of a uranium atom is 238 and the relative mass of a fluorine atom is 19, calculate the number of fluorine atoms that are combined with one uranium atom.