can someone please help me with this question for chemistry. What is the number of moles in 1216 g Sr3(PO4)2? the 3,4, and 2 and small numbers that go under the letters btw

17) large amounts of very important metal titanium are made by reacting magnesium metal with titanium tetrachloride. titanium metal and magnesium chloride are produced. a) write the balanced equation for this reaction. b) how many kilograms of magnesium are required to produce 1.00 kilograms of titanium? ( show work, .)