1. ENTRY QUIZ LecturePLUS Timberlake1 1.How many elements do you know? 2.What are they? 3.Which of them are inert gases? 4.Which are metals? 5.Which are metalloids?

2. 12 th element LecturePLUS Timberlake2 Magnesium Mg Atomic number 12 Atomic weight 24.31 Alkaline metal, reactive, paramagnetic 3 isotopes: 12 neutrons, 13 isotopes, 14 isotopes Atomic structure: 12 p, 12 e, 12 n

3. LecturePLUS Timberlake3 Writing a Chemical Equation Chemical symbols give a “before-and-after” picture of a chemical reaction ReactantsProducts MgO + CCO + Mg magnesium oxide to form carbon monoxide reacts with carbon and magnesium

4. LecturePLUS Timberlake4 Learning Check E3 12 oz of dough, 4 oz mushrooms, 12 slices pepperoni, 8 oz cheese and 5 oz tomato sauce are used to make a pizza. Write a recipe in words for putting together a pizza. How would you write the recipe as an equation?

5. LecturePLUS Timberlake5 Solution E3 Example: Combine 12 oz dough + 4 oz mushrooms + 12 slices pepperoni + 8 oz cheese + 5 oz tomato sauce and heat 30 minutes at 350°C to produce 1 pizza 12 oz dough + 4 oz mshrm + 12 pep + 8 oz chse 1 pizza + 5 oz tom sauce

6. LecturePLUS Timberlake6 Reading A Chemical Equation 4 NH 3 + 5 O 2 4 NO + 6 H 2 O Four molecules of NH 3 react with five molecules O 2 to produce four molecules NO and six molecules of H 2 O or Four moles NH 3 react with 5 moles O 2 to produce four moles NO and six moles H 2 O

7. LecturePLUS Timberlake7 A Balanced Chemical Equation Same numbers of each type of atom on each side of the equation Al + S Al 2 S 3 Not Balanced 2Al + 3S Al 2 S 3 Balanced

8. LecturePLUS Timberlake8 Matter Is Conserved H 2 + Cl 2 2 HCl ++ Total atoms=Total atoms 2 H, 2 Cl2H, 2 Cl Total Mass=Total Mass 2(1.0) + 2(35.5)2(36.5) 73.0 g=73.0 g

9. LecturePLUS Timberlake9 Law of Conservation of Mass In any ordinary chemical reaction, matter is not created nor destroyed

10. LecturePLUS Timberlake10 Balance Equations with Coefficients Coefficients in front of formulas balance each type of atom 4NH 3 + 5O 2 4NO + 6H 2 O 4 N = 4 N 12 H=12 H 10 O=10 O

11. LecturePLUS Timberlake11 Steps in Balancing An Equation Fe 3 O 4 + H 2 Fe + H 2 O Fe: Fe 3 O 4 + H 2 3 Fe + H 2 O O:Fe 3 O 4 + H 2 3 Fe + 4 H 2 O H: Fe 3 O 4 + 4 H 2 3 Fe + 4 H 2 O

12. LecturePLUS Timberlake12 Learning Check E4 Fe 3 O 4 + 4 H 2 3 Fe + 4 H 2 O A. Number of H atoms in 4 H 2 O 1) 22) 43) 8 B. Number of O atoms in 4 H 2 O 1) 22) 43) 8 C. Number of Fe atoms in Fe 3 O 4 1) 12) 33) 4

13. LecturePLUS Timberlake13 Solution E4 Fe 3 O 4 + 4 H 2 3 Fe + 4 H 2 O A. Number of H atoms in 4 H 2 O 3) 8 B. Number of O atoms in 4 H 2 O 2) 4 C. Number of Fe atoms in Fe 3 O 4 2) 3

14. LecturePLUS Timberlake14 Learning Check E5 Balance each equation. The coefficients for each equation are read from left to right A. Mg + N 2 Mg 3 N 2 1) 1, 3, 2 2) 3, 1, 2 3) 3, 1, 1 B. Al + Cl 2 AlCl 3 1) 3, 3, 22) 1, 3, 13) 2, 3, 2

15. LecturePLUS Timberlake15 Learning Check E5 C. Fe 2 O 3 + C Fe + CO 2 1) 2, 3, 2,3 2) 2, 3, 4, 3 3) 1, 1, 2, 3 D. Al + FeO Fe + Al 2 O 3 1) 2, 3, 3, 1 2) 2, 1, 1, 1 3) 3, 3, 3, 1 E. Al + H 2 SO 4 Al 2 (SO 4 ) 3 + H 2 1) 3, 2, 1, 2 2) 2, 3, 1, 3 3) 2, 3, 2, 3

16. LecturePLUS Timberlake16 Solution E5 A. 3 Mg +N 2 Mg 3 N 2 B. 2 Al + 3 Cl 2 2 AlCl 3 C. 2 Fe 2 O 3 + 3 C 4 Fe + 3 CO 2 D. 2 Al + 3 FeO 3 Fe + Al 2 O 3 E. 2 Al + 3 H 2 SO 4 Al 2 (SO 4 ) 3 + 3 H 2

17. Activity 2. Metals with chloric acids. Balance equations! LecturePLUS Timberlake17 1.Li + HCl --  LiCl + H2 2.Na + HCl --  NaCl + H2 3.K + HCl --  KCl + H2 4.Rb + HCl --  RbCl + H2 5.Cs + HCl --  CsCl + H2 6.Be + HCl --  BeCl2 + H2 7.Mg + HCl ---  MgCl2 + H2 8.Ca + HCl ---  CaCl2 + H2 9.Sr + HCl ---  SrCl2 + H2 10.Ba + HCl --  BaCl2 + H2 11.Al + HCl --  AlCl3 + H2 12.Fe + HCl --  FeCl3 + H2

18. EXIT QUIZ LecturePLUS Timberlake18 1.What is to balance equations? 2.What type of conservation do you see? 3.What is balance at the left? 4.What is balance at the right? 5.Are they equal?