1. Types of Reactions Na 2 CO 3(aq) + CaCl 2(aq)  2NaCl (aq) + CaCO 3(s) 1. Precipitation 2. Acid - Base 3. Oxidation – Reduction (Redox)

2. Acids & Bases (Bronsted) Acid = Proton (H + ) donor Base = Proton acceptor Acid Properties: sour (vinegar and citrus fruit) turns litmus red

3. Strong Acids HCl, HNO 3 , H 2 SO 4 HCl (aq)  H + (aq) + Cl - (aq) or ….. HCl + H 2 O (l)  H 3 O + (aq) + Cl - (aq) There is no HCl present in solution proton hydronium ion monoprotic diprotic

4. Weak Acids HCN (aq)  H + (aq) + CN - (aq) HCN, H + and CN - are present in solution H 2 O (l)  H + (aq) + OH - (aq) All aqueous solutions will contain protons and hydroxide ions. Acetic acid = H(C 2 H 3 O 2 ) Phosphoric Acid = H 3 PO 4

5. Base Properties: bitter slippery turns litmus blue Strong bases: NaOH; KOH Weak bases: NH 3 , CO 3 2-

6. Neutralization Reactions Acid + Base  salt + H 2 O HNO 3(aq) + KOH (aq)  KNO 3(aq) + H 2 O (l) HCl (aq) + Na 2 CO 3(aq)  KNO 3(aq) + CO 2(g) + H 2 O (l)

7. Oxidation Reduction Reactions (Redox) Transfer of electrons (between atoms in compounds) oxidation = loss of electrons reduction = gain of electrons oxidizing agent – gets reduced by accepting electrons reducing agent – gets oxidized by donating electrons

8. Oxidation State - Rules 1. 0 in elemental form (e.g. H 2 , O 2 , Zn (s) ) 2. Ion charge = oxidation state for ions (of elements ) 3. O = -2 (except in peroxides, e.g. H 2 O 2 ) 4. H = +1 (except as hydride in ionic cpd) 5. F = -1 (other halides = -1 if ionic cpd) 6. Sum of ox #s = charge of ion or 0 for neutral cpd

9. Oxidation-Reduction Reactions Any combustion reaction cpd of (CHO) + O 2  CO 2 + H 2 O example methane combustion …. Reaction of acid with metals …. 2HCl (aq) + Zn (s)  ZnCl 2(aq) + H 2(g)  __Al (s) + __Fe 2 O 3(s)  __Fe (s) + __Al 2 O 3(s) + heat

11. Blood Alcohol Levels Legal limit = 0.1% by mass/(weight) What is approximate Molarity? ethanol ~ 46.0 g mol -1 How much dilution of 3.2% beer results in this? Why is this misleading?

12. Breath Analyzer ___C 2 H 6 O + ___ K 2 Cr 2 O 7 + ___ H 2 SO 4  ___C 2 H 4 O 2 + ___ Cr 2 (SO 4 ) 3 + ___ K 2 SO 4 + ___ H 2 O

13. Getting Mg from seawater 1. CaCO 3(s)  CaO (s) + CO 2(g) 2. CaO (s) + H 2 O (l)  + Ca 2+ (aq) + 2OH - (aq) 3. Mg 2+ (aq) + 2OH - (aq)  MgOH 2(s) 4. MgOH 2(s) + HCl (aq)  MgCl 2(aq) + 2H 2 O (l) 5. MgCl 2(l) + e -  Mg (l) + Cl 2(g) 