1. Formula (Molar) Mass Li Mn K

2. Formula (Molar) Mass Add atomic mass of each atom in formula Unit: g/mol Mass of one mole of a pure substance

3. Formula (Molar) Mass NaCl Na 2 SO 4 (NH 4 ) 2 S

4. Grams to Moles to Particles Molar mass in grams =1 mole= 6.022 x 10 23

5. Mole SI base unit Unit: mol Amount of a substance that contains as many particles as there are atoms in 12g of C. 1 mole = 6.022 x 10 23 particles

6. Mole Grams 0.0135 mol Na = ? g 3.5 mol NaOH = ? g 11.9 g Al = ? mol 0.053 08 g Mg 3 (PO 4 ) 2 = ? mol Use Molar Mass to convert

7. Avogadro’s Number 6.022 x 10 23 Unit: atoms, formula units, molecules, ions Number of particles in 1 mol of substance

8. Mole Particles 2500 atoms Sn = ? mol 3.01 x 10 23 molecules AgCl = ? mol 2.75 mol Al = ? atoms. Determine the number of molecules in 8.0 mol H 2 O.

9. Molar Mass Avogadro’s # Grams Mole Particles

10. 1.20 x 10 8 atoms Cu = ? g 7.2 x 10 24 molecules= ? g Ca(OH) 2. Determine the number of molecules of H 2 S in 43.92 g.

11. Percent Composition 1.Find M.M. of elements 1.Find M.M. of compound 1.molar mass of element x 100 = % composition molar mass of compound

12. Percent Composition % of C in CO 2 % of H and O in H 2 SO 4 % of Na and S in Na 2 SO 4

13. Homework 1.Find the formula weight of NaCl. 2.Determine the number of moles of CO 2 in 454 grams. 3.Determine the mass in grams of 3.60 mol of H 2 SO 4. 4.Determine the mass in grams of 3.01 x 10 23 atoms of H 2 O. 5.Find the % of Oxygen in Na 2 SO 4.

14. Practice 1. Find the Molar Mass of H 2 S. 2. Find the Molar Mass of Fe(NO 3 ) 2.

15. Practice 3. Determine the number of moles in 15 grams of OH. 4. Determine the number of grams in 8.42 x 10 21 atoms of Br 2. 5. Determine the number of molecules in 6.75 moles of O 2. 6. Determine the number of atoms in 11.5 grams of N.

16. Practice 7. Determine the number of grams in 5 moles of S. 8. Determine the number of moles in 40.1 grams of H 2 O. 9. Determine the number of moles in 250 grams of NaCl. 10. Determine the number of grams in 3.011 x 10 23 molecules Li 2 O.

17. Practice 11. Find the % mass of H in NH 3 12. Find the % mass of O in MgO.

18. Answers to Practice 1.34.086 g/mol H 2 S 2.179.89 g/mol Fe(NO 3 ) 2 3.0.88 mol OH 4.2.23 g Br 2 5.4.06 x 10 24 molecules O 2 6.4.94 x 10 23 atoms N 7.160. 35 g S 8.2.23 mol H 2 O

19. Answers to Practice 9. 4.28 mol NaCl 10. 14.94 g Li 2 O 11. 17.75% H 12. 39.69% O