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Chem 332 – O’Dette. Two step Mole Problems. Review!!!. How many moles are in 4.2x10 16 atoms of silver? 7.0x10 -8 moles Ag How many grams are in 9.0 moles of ammonium fluoride? 330 grams NH 4 F. Why do we need moles???. You can NOT directly convert from grams to particles!!!
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Chem 332 – O’Dette Two step Mole Problems
Review!!! • How many moles are in 4.2x1016 atoms of silver? • 7.0x10-8 moles Ag • How many grams are in 9.0 moles of ammonium fluoride? • 330 grams NH4F
Why do we need moles??? • You can NOT directly convert from grams to particles!!! • You must go through MOLES!!!!
Mole Bridge Avogadro’s Number Grams Moles Particles MM 1 gram 1 mole 6.022x1023 particles 1 mole
Ex: How many atoms of Cu are present in 35.4 grams of Cu? 6.022x1023 atoms 1 mole 35.4 g x x = 3.35 x1023 atoms Cu 1 mole 63.55 g Cu MM AN
What is the mass of 1.20x1024 molecules of glucose (C6H12O6)? • You are going to need the molar mass of glucose!!!! • MM = 180.18 g glucose/mole 1.20x1024 molecules x 1 mole x 180.18 g 1 mole 6.022x1023molecules AN MM = 359 g C6H12O6