Question

problem set 6

2. Magnetite Fe,O, is an iron containing ore. How many moles of iron atoms would be found in 2.5 moles of magnetite? How many atoms of iron would this be? Show all work 3. Consider the following pairs. For each pair, circle the quantity that contains the greater number of atoms or molecules Then explain your reasoning a) 1 mole Na or 1 gram Na b) 1 molecule of lz or 1 mole of la C) 58.9 grams Co or 58.9 grams Cu d) 1 gram atomic weight of Pb or 1 gram of Pb 4. A drop of water (H2O) has a mas of 0.050 grams. How many molecules of H20 are present? Show all work

Answer 1

191140Dall m 6 7 H1402 Hone grom molecular weight = 19 x me + 14 x an H + 2x mo] = 7x12 + 14x 1.0 of 2x 16] = 130 grams. H = 1 g mass tq GH1402 = #1402 molecular weigles in 130 g/mole I mole - 6.023 x 1023 Solnavos 7.69 x 10-3 mole . Number of molecules = 7.69x10 3 x 6.023 x 1023 = 4.63 X 1021 molecules 1.0 g = 10 6 a bount bood Number of molecules = 4.63x1021 x 10-6 = 4.63 x 10 15 molecules @