1. WHERE DO YOU LOOK IF YOU’VE LOST YOUR MIND? -Bernard Malamud-

2. REVIEW WHAT INFORMATION DOES THE FOLLOWING FORMULA TELL YOU? 2 (NH 4 ) 3 PO 4

3. WHAT INFORMATION DOES THE FOLLOWING FORMULA TELL YOU? 2 (NH 4 ) 3 PO 4 1)You have 2 formula units of ammonium phosphate, or 2)You have 2 moles of ammonium phosphate 3)In those 2 formula units, you have 6 atoms of nitrogen, 24 atoms of hydrogen, 2 atoms of phosphorus, 8 atoms of oxygen, or 4)In those 2 moles, you have 6 moles of nitrogen, 24 moles of hydrogen, 2 moles of phosphorus, and 8 moles of oxygen

4. CALCULATE THE MOLAR MASS OF ZnSO 4.

5. 1 Zn = 1 x 65 = 65 1 S = 1 x 32 = 32 4 O = 4 x 16 = 64 Molar Mass = 161 g/mole

6. HOW MANY MOLES OF K 2 SO 4 ARE IN 20 GRAMS?

7. First, calculate the molar mass: K = 2 x 39 = 78 S = 1 x 32 = 32 O = 4 x 16 = 64 Molar mass = 174 g/mole # moles = 20 g / 174 g/mole = 0.115 mole

8. HOW MANY MOLECULES OF C 2 H 5 OH ARE IN 2.5 MOLES?

9. 1 mole = 6.023 x 10 23 molecules # molecules = 2.5 moles x 6.023 x 10 23 molecules/mole = 1.51 x 10 24 molecules

10. HOW MANY GRAMS OF PbI 2 ARE IN 8.4 X 10 22 MOLECULES?

11. # moles = 8.4 x 10 22 / 6.023 x 10 23 = 1.39 x 10 -1 = 0.139 moles Molar mass of PbI 2 = 207 + 2(127) = 461 g/mole # grams = 461 g/mole x 0.139 moles = 64 g

12. BALANCE THE FOLLOWING EQUATIONS, AND TELL WHAT KIND OF REACTION THE EQUATION REPRESENTS: a.C 4 H 10 + O 2 → CO 2 + H 2 O b.Fe + Cl 2  FeCl 3 c.Cu + AgNO 3  Cu(NO 3 ) 2 + Ag d.Pb(NO 3 ) 2 + AlCl 3  Al(NO 3 ) 3 + PbCl 2 e.KClO 3  KCl + O 2

13. BALANCE THE FOLLOWING EQUATIONS, AND TELL WHAT KIND OF REACTION THE EQUATION REPRESENTS: a.2 C 4 H 10 + 13 O 2 → 8 CO 2 + 10 H 2 O b.2 Fe + 3 Cl 2  2 FeCl 3 c.Cu + 2 AgNO 3  Cu(NO 3 ) 2 + 2 Ag d.3 Pb(NO 3 ) 2 + 2 AlCl 3  2 Al(NO 3 ) 3 + 3 PbCl 2 e.2 KClO 3  2 KCl + 3 O 2

14. WHAT ARE THE SUBSTANCES ON THE LEFT SIDE OF A CHEMICAL REACTION CALLED? WHAT ARE THE SUBSTANCES ON THE RIGHT SIDE OF CHEMICAL REACTION CALLED?

15. WHAT ARE THE SUBSTANCES ON THE LEFT SIDE OF A CHEMICAL REACTION CALLED? REACTANTS WHAT ARE THE SUBSTANCES ON THE RIGHT SIDE OF CHEMICAL REACTION CALLED? PRODUCTS

16. WHAT IS THE LAW OF CONSERVATION OF MASS?

17. IN A CHEMICAL REACTION, MATTER IS NEITHER CREATED OR DESTROYED, ONLY REARRANGED.

18. HOW DOES THE LAW OF CONSERVATION OF MASS APPLY TO A CHEMICAL EQUATION?

19. YOU HAVE THE SAME NUMBER OF EACH TYPE OF ATOMS ON BOTH SIDES OF THE EQUATION – THE EQUATION IS BALANCED.

20. 2 NH 3 + H 2 SO 4  (NH 4 ) 2 SO 4 How many grams of ammonia (NH 3 ) would be required to make 1 kilogram of ammonium sulfate?

21. X 1000 g 2 NH 3 + H 2 SO 4  (NH 4 ) 2 SO 4 34128 X / 34 = 1000 / 128 X = (1000 x 34) / 128 = 265.6 g Note: molar mass of ammonium sulfate = 128 g/mole molar mass of ammonia = 17 g/mole

23. How many moles of iron, Fe, would be required to make 40 grams of hydrogen, H 2 ? 2 Fe + 6 HCl  2 FeCl 3 + 3 H 2

24. How many moles of iron, Fe, would be required to make 40 grams of hydrogen, H 2 ? 2 Fe + 6 HCl  2 FeCl 3 + 3 H 2 Molar mass of H 2 = 2 g/mole # moles H 2 = 40 g/2 g/mole = 20 moles X 20 2 Fe + 6 HCl  2 FeCl 3 + 3 H 2 2 3 X/2 = 20/3 so X = 20/3 x 2 = 13.3 moles

25. A COMPOUND CONTAINS THE ELEMENTS COPPER AND CHLORINE IN A RATIO OF 1 COPPER : 2 CHLORINE. WHAT IS THE EMPIRICAL FORMULA FOR THIS COMPOUND? WHAT IS THE % COMPOSITIONOF COPPER? WHAT IS THE % COMPOSITION OF CHLORINE?

26. EMPIRICAL FORMULA: CuCl 2 Molar mass = 63.5 + 2(35.5) = 134.5 g/mole % Cu = (63.5 / 134.5) x 100 = 47.2 % % Cl = (71 / 134.5) x 100 = 52.8 %