2. The Mole Measurement of Matter

3. Measuring Matter How do we measure matter?How do we measure matter? Count, Mass, or VolumeCount, Mass, or Volume Counting: 1 dozen apples = 12 applesCounting: 1 dozen apples = 12 apples Mass: 1 dz. Apples = 2.0 kg applesMass: 1 dz. Apples = 2.0 kg apples Volume: 1 dz. Apples = 0.20 bushels applesVolume: 1 dz. Apples = 0.20 bushels apples

4. Unit Conversions Relating to a dozen allows you to convert between the unitsRelating to a dozen allows you to convert between the units Unit Conversion FactorsUnit Conversion Factors

5. What is the Mole? A counting number (like a dozen)A counting number (like a dozen) Avogadro’s number (N A )Avogadro’s number (N A ) 1 mol = 6.02  10 23 items1 mol = 6.02  10 23 items

6. Size of Moles 1 mole of pennies would cover the Earth 1/4 mile deep!1 mole of pennies would cover the Earth 1/4 mile deep! n n 1 mole of hockey pucks would equal the mass of the moon! n n 1 mole of basketballs would fill a bag the size of the earth!

7. Molar Mass Mass of 1 mole of an element or compound.Mass of 1 mole of an element or compound. Atomic mass tells the...Atomic mass tells the... atomic mass units per atom (amu) atomic mass units per atom (amu) grams per mole (g/mol) grams per mole (g/mol)

8. Molar Mass Examples carboncarbon aluminumaluminum zinczinc 12.01 g/mol 26.98 g/mol 65.39 g/mol

9. Molar Mass Examples waterwater sodium chloridesodium chloride H2OH2O  2(1.01) + 16.00 = 18.02 g/mol  NaCl  22.99 + 35.45 = 58.44 g/mol

10. Molar Mass Examples sodium bicarbonatesodium bicarbonate sucrosesucrose  NaHCO 3  22.99 + 1.01 + 12.01 + 3(16.00) = 84.01 g/mol  C 12 H 22 O 11  12(12.01) + 22(1.01) + 11(16.00) = 342.34 g/mol

11. Molar Conversions molar mass (g/mol) MASS IN GRAMS MOLES NUMBER OF PARTICLES 6.02  10 23 (particles/mol)

12. Molar Conversion Examples How many moles of carbon are in 26 g of carbon?How many moles of carbon are in 26 g of carbon? 26 g C 1 mol C 12.01 g C = 2.2 mol C

13. Molar Conversion Examples How many molecules are in 2.50 moles of C 12 H 22 O 11 ?How many molecules are in 2.50 moles of C 12 H 22 O 11 ? 2.50 mol 6.02  10 23 molecules 1 mol = 1.51  10 24 molecules C 12 H 22 O 11

14. Molar Conversion Examples Find the mass of 2.1  10 24 molecules of NaHCO 3.Find the mass of 2.1  10 24 molecules of NaHCO 3. 2.1  10 24 molecules 1 mol 6.02  10 23 molecules = 290 g NaHCO 3 84.01 g 1 mol

15. Mole: unit for defining a group of atomsMole: unit for defining a group of atoms Avogadro’s number = 6.022 x 10 23Avogadro’s number = 6.022 x 10 23 1 mole of atoms = 6.022 x 10 23 atoms1 mole of atoms = 6.022 x 10 23 atoms Molar mass - The mass (g) of 1 mole of atomsMolar mass - The mass (g) of 1 mole of atoms What is the molar mass of carbon? 12.01 g/mol CWhat is the molar mass of carbon? 12.01 g/mol C One mole of any element contains the same number of atoms, 6.022 x 10 23, Avogadro’s numberOne mole of any element contains the same number of atoms, 6.022 x 10 23, Avogadro’s number The Mole and Avogadro’s Number

16. Practice Calculations 1.Calculate the number of atoms in 1.7 moles of boron. 2.Find the mass in grams of 2.5 mol Na (sodium). 3.Calculate the number of atoms in 5.0 g aluminum. 4.Calculate the mass of 5,000,000 atoms of Au (gold)