1. 1)0.00045 2)3.4 x 10 -5 3)0.001 4)5.6 x 10 3 Remembering Scientific Notation…..

3.  Main unit in chemistry we will use ! ! !  Describes the amount of atoms in a particular substance  1 mole = 6.02 x 10 23 atoms (KNOW THIS CONVERSION)  1 mole = formula mass (g) of a compound = atomic mass (g) of an element = 22.4 L of a solution under STP The MOLEThe MOLE

4. Example 1: CarbonExample 1: Carbon

5. Example 2: AluminumExample 2: Aluminum

6.  = mass of 1 mole of a substance  Units = grams/mole or g/mol Molar MassMolar Mass

7. 1 mole = 6.02 x 10 23 atoms “Avogadro’s number” How many atoms are in 1 mole?

8.  How many atoms are in 1 mole of Mg? Example 1Example 1

9.  How many atoms are in 1 mole of C? Example 2:Example 2:

11. Remember…..  1 mole =  6.02 x 10 23 atoms of element/molecules of chemical compound  Atomic mass of element  Formula mass of a compound

12. Example 1:Example 1:  2 moles Carbon grams

13. Example 2:Example 2:  Calcium has a mass of 10.0g. How many moles of Calcium? Atoms?

14. Example 3:Example 3:  86.2 grams C 2 H 4. How many moles of C 2 H 4 ? How many molecules?

15. Example 4:Example 4:  1.26 moles of NbI 5. How many grams?

16. Example 5:Example 5:  5 grams of H 2 O to molecules of H 2 O

17. Practice  Mole Conversion Worksheet