The document discusses mole conversions between number of atoms/molecules, moles, and grams. It provides shortcuts for common conversions between these units and works through sample problems converting between atoms, molecules, moles, and grams of various substances using their molar masses.

1. Using the mole for… CONVERSIONS

2. CONVERSIONS Must use the molar mass Can go from: # of atoms/molecules to moles Moles to # of atoms/molecules moles to grams grams to moles

3. SHORTCUTS for CONVERSIONS Moles to atom/molecules moles times 6.022 x 10 23 Atom/molecules to moles # of atoms or molecules divided by 6.022 x 10 23 Moles to grams moles times molar mass Grams to moles grams divided by molar mass

4. mole island atom island gram island liter island Divide by 22.4L Mult by 22.4L Divide by molar mass Mult by molar mass divide by 6.022 x 10 23 Mult by 6.022 x 10 23

5. Mole GRAMS LITERS # of atoms Divide by 6.022 x 10 23 X by 6.022 x 10 23 X by 22.4 liters Divide by 22.4 liters Divide by molar mass X by molar mass

6. Sample problems How many atoms of copper are found in 1.34 moles of copper? We are on mole island, need to get to atoms island. Multiply moles by 6.022 x 10 23 1.34 x 6.022 x 10 23 = 8.07 x 10 23 atoms of copper

7. How many moles does 1.23 x 10 23 molecules of CaCl 2 represent? we are on atom/molecule island, need to get to mole island. divide # of molecules by 6.022 x 10 23 1.23 x 10 23 / 6.022 x 10 23 = .20 moles of CaCl 2

8. How many grams are in 3.4 moles of I 2 ? We are on mole island, need to get to grams island. multiply # of moles by the molar mass 3.4 x 253.8 = 862.92 grams of I 2

9. How many moles does 134.7 grams of H 2 SO 4 equal? We are on gram island, need to get to mole island. divide # of grams by the molar mass 134.7 / 98.08 = 1.37 moles of H 2 SO 4

10. How much does 7.12 x 10 24 molecules of H 2 O weigh in grams? We are on atoms/molecules island, need to get to gram island. divide # of molecules by 6.022 x 10 23 then multiply by the molar mass (7.12 x 10 24 /6.022 x 10 23 ) x 18.02 = 213.06 grams of water

11. HOMEWORK 1. How many moles are found in a sample containing 6.02 x 10 24 atoms? 2. If you have 1.28 x 10 22 molecules of HCl, how many moles do you have? 3. 3.5 moles of gold would have how many atoms? 4. If you had 12.3 moles of baking soda, how many molecules would it contain? 5. A sample of NaCl weighing 1.25 grams contains how many molecules?

12. MORE HOMEWORK 6. Calculate the number of moles in a 15.3 gram sample of barium hydroxide. 7. How many grams does 0.14 moles of silver nitrate equal? 8. If you had 2.3 grams of aluminum, how many atoms would it contain? 9. If you had 3.4 x 10 34 atoms of tungsten(V) arsenate, how many moles would you have? How many grams?