The number of grams present in 1.35 mol of Fe is

First you need to find the mass of one mole of the element. (say Fe) Find Fe on the periodic table, it should tell you what the average atomic mass is. The average atomic mass = mass of one mole. (in this case it is 55.85g) Take your moles (1.35mol Fe) and multiply it by the mass of one mole (55.85g) 1.35mol*55.85g/mol=75.39g (Just repeat that method for the other problems) use the formula moles = mass Molar mass