1. Chapter 10 Chemical Reactions

2. Types of Chemical Reactions 1)Oxidation-Reduction (Redox) 2) Combination 3) Decomposition 4) Replacement 5) Ion Exchange

3. 2 KI + Pb(NO 3 ) 2 → PbI 2 ↓ + 2 KNO 3 PbI 2 (s) Pg 251 KI (aq)

4. Ion Exchange Reaction – ions of one compound react with ions of another compound to form: (1) a solid (precipitate) or FeCl 3 + 3 NaOH → Fe(OH) 3 + 3 NaCl (2) a gas or(3) water CaCO 3 + 2 HCl → CaCl 2 + CO 2 ↑ + H 2 O

5. By definition: 1 atom 12 C “weighs” 12 u On this scale 1 H = 1.008 u 16 O = 16.00 u Atomic mass ≡ mass of an atom in atomic mass units (u) Micro World atoms & molecules Macro World (grams)

6. Natural lithium is: 7.42% 6 Li (6.015 u) 92.58% 7 Li (7.016 u) (7.42 · 6.015) + (92.58 · 7.016) 100 = 6.941 u Average atomic mass of lithium:

7. Average atomic mass (6.941)

8. mole - the amount of a substance that contains as many particles as there are atoms in exactly 12.00 grams of 12 C 1 mol = N A = 6.02 x 10 23 Avogadro’s number (N A )UNITS

9. Molar mass - the mass of 1 mole of in grams eggs shoes marbles atoms 1 mole 12 C atoms = 6.022 x 10 23 atoms = 12.00 g 1 12 C atom = 12.00 u 1 mole 12 C atoms = 12.00 g 12 C 1 mole lithium atoms = 6.941 g of Li For any element atomic mass (u) = molar mass (grams)

10. 10 One Mole of: C S Cu Fe Hg

11. 11 Molecular mass (or molecular weight) - the sum of the atomic masses (in u) in a molecule. SO 2 1S32.07 u 2O+ 2 x 16.00 u SO 2 64.07 u For any molecule molecular mass (u) = molar mass (grams) 1 molecule SO 2 = 64.07 u 1 mole SO 2 = 64.07 g SO 2

12. 12 Fig 10.16 The mole concept for: (A)Elements: (B) Compounds: (C) Molecular substances:

13. 13