1. The Mole Chapter 10

2. What is a mole? A conversion factor used in chemistry to make it easier to talk about a very large amount of particles of elements or compounds. 1 dozen bagels= 12 bagels 1 mole bagels= 6.02 X 10 23 bagels

3. Avogadro’s Number Avogadro’s # = 6.02 x 10 23 units 1 mole= Avogadro’s number = 6.02 x 10 23 units “Units” can be anything but in chemistry these units are referred to as: Particles Atoms Molecules Formula Units

4. Examples 1 mole of Fe= 6.02 x 10 23 atoms Fe 1 mole sugar= 6.02 x 10 23 molecules of sugar 1 mole BeF 2 = 6.02 x 10 23 formula units of BeF 2

5. Moles to Particles Conversions Think back to dimensional analysis How many atoms of carbon make up 6.80 moles of carbon?

6. Moles to Particles How many formula units of potassium phosphate make up 1.3 moles?

7. Particles to Moles How many moles make up 5.60 x 10 25 atoms of copper?

8. Particles to Moles 25 molecules of carbon tetrahydride= ? moles

10. How does mass relate to the mole? What does an amu (atomic mass unit) measure? 1 amu= 1.66053886 x 10 -27 kilograms A relative scale used to measure the mass of single elements or compounds

11. Learning the terminology… Atomic mass- measure the mass of a single atom in amu’s Example: 1 atom Fe= 55.85 amu ***Always go to the hundredths place when taking masses from the periodic table.

12. Formula mass- measures the mass of a single formula unit (ionic compounds) in amu’s – Example: 1 formula unit BeF 2 = Molecular mass- measures the mass of a single molecule (covalent) in amu’s – Example: 1 molecule of C 12 H 22 O 11 =

13. Molar Mass The mass of 1 mole of any substance in grams – Example: 1 atom Fe= 55.85 amu 1 mole Fe= 55.85 g 1 molecule of sugar= 342.34 amu 1 mole of sugar= 342.34 g

14. Moles to Grams Conversion Remember… molar mass can be used as a conversion for any type of particle. 12.01 grams C = 1 mole C 58.44 grams NaCl= 1 mole NaCl 44.01 grams CO 2 = 1 mole CO 2

15. Moles to Grams How many grams is 4.672 moles of barium chloride?

16. Grams to Moles 0.0025 g disulfur trioxide = ? mole

18. Grams to Particles Converting This is a 2-step process. You must ALWAYS go through the mole first

19. Grams to Particles How many atoms of platinum are needed to obtain 15.00g of Pt?

20. Particles to Grams What is the mass of 2.77 x 10 13 molecules of oxygen?

21. Liters to Mole Conversions Liters (L) are a volume unit of measurement STP= standard temperature and pressure conditions (0° and 1 atm) This conversion only may be used when: At STP conditions Working with gases 1 mole = 22.4 L of gas @ STP

22. Liters to Moles How many moles of chlorine gas @ STP take up 4.9 L of space?

23. Moles to Liters How much space does 0.359 moles of carbon monoxide gas take up @ STP?

24. Liters to Particles This is a 2-step process. You must ALWAYS go through the mole first

25. Liters to Particles How many molecules of iodine gas take up 3.56 L of space @ STP

26. Particles to Liters How much space does 3.5 x 1022 molecules of nitrogen dioxide gas take up @ STP?

27. Liters to Grams Converting This is a 2-step process. You must ALWAYS go through the mole first.

28. Liters to Grams What is the mass of 0.57 L of hydrogen gas @ STP?

29. Grams to Liters How much space does 5 x 10 5 g of water vapor take up @ STP?