1. PRS Questions: Acid-Base reactions
CH3CO2H(aq) + NaOH(aq) 
1. CH3CO2H2+(aq) + NaO(aq)
2. CH3CO2-(aq) + H2O(l) + Na+(aq)
3. CH4(g) + CO2(g) + H2O(l)

2. PRS Questions: Acid-Base reactions
HCN(aq) + NH3(aq) 
1. NH4+(aq) + CN-(aq)
2. H2CN+(aq) + NH2-(aq)
3. C2N2(s) + 3 H2(g)

3. Precipitation Reactions
Solubility of Ionic Compounds
dissolving

4. To Determine Solubility:
1. identify the two ions
2. soluble ions with no “exceptions” never
form precipitates
3. use listing under soluble/insoluble, but
check to see if it’s an exception

5. Examples
Soluble or Insoluble?
NaNO3
FeCl3
Fe(OH)3
BaSO4
AgNO3
AgCl

6. More Examples Soluble or Insoluble? K3PO4 Fe3(PO4)2 PbCl2 FeSO4
(NH4)2S
PbS

7. PRS Example 1 Which of the following is soluble? AlPO4 PbBr2 Al(OH)3
FeSO4

8. PRS Example 2 Which of the following is insoluble? Al(NO3)3 PbC2O4
NaOH
FeF3

9. Precipitation Reactions Net Ionic Equations
Pb(NO3)2 + K2CrO4  ?
Pb(NO3)2 + KI  ?

10. Precipitation Reactions Net Ionic Equations
Pb(NO3)2 + K2CrO4  ?
Pb(NO3)2 + KI  ?
BaCl2 + KNO3 

11. Return to Acid-Base Reactions: Find the hidden bases
Thing to know: Anions of weak acids are bases.
Example: CH3COOH = weak acid
CH3COO- therefore = weak base
HCN = weak acid
CN- = weak base
H3PO4 = weak acid
PO43- = weak base

12. Return to Acid-Base Reactions: Find the hidden bases
HCl + NaCN  ?
HCl + AlPO4  ?
HCl + CaC2O4  ?

13. Gas Forming Reactions 2 H+ + CO32-  CO2(g) + H2O(l)
2 H+ + SO32-  SO2(g) + H2O(l)
2 H+ + M  H2(g) + M2+(aq)
M = metal, like Mg or Fe