1. T HE M OLE Chapter 7

2. C ONCEPT M AP The mole Can be converted to Similar to: Dozen/ Gross/ set/ pair 6.02x10 ^23 Particles- atoms, molecules, etc. Molar Mass Mass- g,mg,kg,etc.

3. M OLAR M ASS Molar Mass = # OF GRAMS 1 MOLE How to calculate Molar Mass- ~ Average atomic mass for each element is on the periodic table 1. Count the number of atoms for each element 2.Multiply the number of atoms by the avg. atomic mass 3.Add together all the atomic masses Example: H 2 O=H: 2 (1.001794 g/mol)= 2.003588 O: 1 (15.9994 g/mol) = 15.9994 18.002988 g/mol

4. A VOGADRO ’ S NUMBER A counting number used to tell how many particles. Avogadro’s number = 6.02 x10 ^23 ‘atoms’ 1 mole Just like there are 12 eggs in a dozen, there are 6.02 x 10^23 eggs in a mole. It is a constant!

5. C ONVERT FROM GRAMS TO MOLES # of grams x 1 mole = # of moles molar mass (g) Example: How many moles are in 25 grams of water? 25 grams x 1 mole = 1.38 moles 18 grams Molar Mass of H 2 O= H: 2x 1.01= 2.02 O: 1x 15.99=15.99 18.01~ 18 g/mol

6. C ONVERT FROM MOLES TO GRAMS # of moles x molar mass (g) = # grams 1 mole Example: How many grams are in 30 moles of water? 30 moles x 18 grams = 540 grams 1 mole

7. C ONVERT FROM GRAMS TO ATOMS OR MOLECULES # of grams x 1 mole x 6.02x10^23atoms = # atoms molar mass 1 mole Molecule= compound Atoms= one element Example: How many molecules of NaCl are in 15 grams? 15 grams x 1 mole x 6.02 x 10^23 molecules=1.55x10^23molecules 58 grams 1 mole Molar Mass of NaCl: Na: 1x 22.989 = 22.989 g Cl: 1x 35.45 =35.45g 58.43 ~ 58 g/mole

8. C ONVERT FROM MOLES TO ATOMS / MOLECULES #moles x 6.02x10^23 atoms = # of atoms 1 mole Example: How many atoms are in 5 moles of NaCl? 5 moles x 6.02x10^23 atoms = 3.01 x10^24 1mole