1. Could you determine the amount of atoms in this block of aluminum?

2. What information would you need? The periodic table has a secret! It can tell you the amount of atoms in a specific mass of each element

3.  Look at the amu of aluminum. The amu also describes the number of atoms in a specific mass in g  Ex: There are 6.02 X10 23 atoms/26.98 g of aluminum  Could you determine the amount of atoms in any piece of aluminum?  Go ahead…..

4.  6.02 X10 23 is a huge number!!!  It is a unit of measurement that scientists use. Just as chefs use the dozen (12)  This is manageable because atoms are so tiny  They call this number a mole!! (sometimes abbreviated mol)  With this new information could you determine the amount of moles if I gave you a specific mass of an element?  Write a conversion you could use.  Ex If I have.500g H 1mol/1.008g How many mols do I have try it… .500g H 1 mol/1.008g =.496 mols of H

5.  If I gave you the amount of mols could you give me the mass? .496 mols of H.1.008g H/mol =.500g H  If I gave you the number of atoms could you determine the mass?  Remember there are 6.02 X10 23 atoms in a mol and the molar mass is the mass of one mole  Find the mass of 2.03 X10 23 atoms of S  2.03 X10 23 atoms S 1 mol/6.02 X 10 23 atoms S 32.055g S/1 mol  Answer = 10.8 g S

6.  Could you determine the amount of moles if I gave you the amount of atoms?  3.02 X 10 23 atoms of Ca is how many moles?  3.02 X10 23 atoms Ca 1 mol/ 6.02 X 10 23 atoms Ca =.502 mols Ca

7. Could you determine the amount of atoms in a specific amount of moles?  2.3 mols of Sr  2.3 mols 6.02 X 10 23 atoms/1 mol = 1.4 X 10 24 atoms

8. How about the number of atoms in a specific amount of mass?  345 g of Ca  345 g Ca 1 mol/40.078g 6.02 X 10 23 atoms/1 mol