1. Chemistry – Feb 22, 2018 P3 – Nomenclature quiz 5
Pick up 2 handouts when done.
Objective –
Driving forces
Assignment:
Driving forces worksheet 1
Agenda
Homework Review (types)
Types of driving forces
Precipitation reactions
Solubility rules
WB Word Equation practice

2. Driving Force
We can write many kinds of reactions on paper, but for them to actually occur, there must be some kind of driving force. Otherwise a simple mixture will happen with no reaction.
Driving Forces:
Formation of a solid
Formation of water
Formation of a gas
Transfer of electrons
Determines a second classification
Note: Any given reaction may have more than one driving force. But if it has none, it will not happen.

3. 1) Formation of a solid When two ionic solutions are mixed…
Sometimes a solid forms. Reaction happens.
Solid formation is a driving force. Called a precipitation reaction.
Sometimes no reaction happens.
How do you know which? Experiments.
Patterns: Solubility rules
Chapter 7, Unnumbered Figure 1, Page 219

4. Solubility Rules – Observations
All common compounds of alkali and ammonium ions are soluble.
All nitrates, acetates, and chlorates are soluble.
All binary compounds of the halogens with metals are soluble,
except those of Ag, Hg(I), Pb(II).
All sulfates are soluble, except those of Ba, Ca, Sr, Ag, Hg(I), Pb(II).
Carbonates, hydroxides, oxides, and phosphates are insoluble, except for alkali and ammonium ions.
Sulfides are insoluble except for Ba, Ca, Sr, Mg, alkali and ammonium.

5. Solubility Rules: Soluble Ionic (aq)
Compounds Containing:
Important exceptions
NO3-
None
C2H3O2-
ClO3-
Cl-
Ag+, Hg22+ , Pb2+
Br- I-
SO42-
Ag+, Hg22+ , Pb2+, Ba2+, Ca2+, Sr2+

6. Solubility Rules: Insoluble Ionic (s)
Compounds Containing:
Important exceptions
CO32-
NH4+ and alkali ions (Li+, Na+, K+, Rb+…)
O2-
NH4+ and alkali ions
PO43-
OH-
Ba2+, Ca2+, Sr2+, NH4+ and alkali ions
S2-
Ba2+, Ca2+, Sr2+, Mg2+ , NH4+ and alkali ions

7. Solubility Rules (all in one view)
Soluble
Insoluble (Precipitates)
Li+, Na+, K+, NH4+ (primary rule)
NO3-, C2H3O2-, ClO3-
Cl-, Br-, I-
Ag+, Hg22+ , Pb2+
SO42-
Ba2+, Ca2+, Sr2+
CO32-, O2-, PO43-
OH-
Ba2+, Ca2+, Sr2+, Mg2+
S2-

8. Using solubility rules
Use to determine whether a written reaction will actually happen or not by providing the state descriptors
Precipitates are usually a driving force for double displacement reactions between ionic compounds.
If no product is a solid, the reaction does not happen.
Ex: CaCl2 + K2SO4  2 KCl + CaSO4
Ex: 2 LiNO3 + Pb(C2H3O2)2  2 LiC2H3O2 + Pb(NO3)2
Ex: (NH4)2O + AlCl3  NH4Cl + Al2O3
Ex: BaI2 + Na2S  2 NaI + BaS
Soluble
Insoluble (Precipitates)
Li+, Na+, K+, NH4+ (primary rule)
NO3-, C2H3O2-, ClO3-
Cl-, Br-, I-
Ag+, Hg22+ , Pb2+
SO42-
Ba2+, Ca2+, Sr2+
CO32-, O2-, PO43-
OH-
Ba2+, Ca2+, Sr2+, Mg2+
S2-

9. Exit Slip - Homework Exit Slip: none
What’s Due? (Pending assignments to complete.)
Start the Driving Forces Worksheet (Page 1 only determine aq/s then state if no reaction occurs)
What’s Next? (How to prepare for the next day)
Read p473, p , p , p