1. There’s a Quiz in Lab Next Week!!!

3. Wait –
There’s a study guide

4. What about this quiz?? End of C 3 (section 3.7)
Chapter 4 (except (4.4 – oxidation reduction pages and titrations pages
Should bring a calculator and a pencil
Think

5. Top 4 Topics Limiting reactants Ionic compounds in water
Strong/weak acids & bases
Molarity

6. Limiting Reactants Theoretical Yield
% Yield = (Actual/Theoretical) x 100
How much is used, formed, left over

7. Ionic Compounds In water Strong / weak electrolytes Ionic equations
Metathesis reactions
Ion Solubility

8. Strong acids & bases Strong acids/bases are strong electrolytes
Common strong acids (Table 4.2) (memorize)
HCl HBr HI HClO3(chloric) HClO4 (perchloric) HNO3 H2SO4
Common strong bases
Group I metal hydroxides (LiOH, NaOH, KOH, RbOH, CsOH)
Heavy Group II metal hydroxides Ca(OH)2, Sr(OH)2 Ba(OH)2

9. Weak acids & bases Weak acids/bases are weak electrolytes
An acid or base that is not strong is weak
Examples of weak acids:
HF H3PO4 H2SO3 HC7H5O2 HC2H3O2
Example of a weak base: NH3
A molecular substance that is not an acid or base is a nonelectrolyte

10. Molarity
Interconverting molarity, moles, volume
Dilution

11. Top 4 Topics Let’s do some examples!
Limiting reactants
Ionic compounds in water
Strong/weak acids and bases
Molarity

12. Limiting Reactants
Theoretical Yield – how much you expect based upon the amount of reactants.
If one reactant is present in excess, then the other limits how much can be made and is used to determine the theoretical yield.

13. 2H2 + O2  2 H2O If 10 moles of oxygen and 10 moles of hydrogen….
The hydrogen limits the amount of water that can be formed
Based upon 10 moles H2, we can make 10 moles water
Based upon 10 moles O2, we can make 20 moles water.
H2 limits. Theoretical Yield = 10 moles ( 180 g) H2O
At end of reaction, will have 5 moles O2 left over

14. Ionic Compounds In water Strong / weak electrolytes Ionic equations
Metathesis reactions
Ion Solubility

15. Group 1A ( alkali metals) cations soluble
NH4+ soluble
NO3- soluble
CH3CO2- = C2H3O2- = acetate soluble
Will be given a chart for other ions

16. Soluble ionic compounds in water exist as free ions surrounded by water molecules.
Soluble ionic compounds are strong electrolytes
Strong acids or bases (HCl, H2SO4), NaOH) are strong electrolytes
Weak acids or bases (CH3CO2H, acetic acid) are weak electrolytes
Molecules that do not disassociate (CO2, sugar) are non electrolytes.

17. What kind of electrolyte am I?
(NH4)2SO4 ?
Strong HF
Weak
C12H22O11 (sucrose)
Non
NH3

18. potassium sulfate with barium nitrate
2K+(aq) + SO4-2 (aq) + Ba+2 (aq) + 2 NO3- (aq)  2K+(aq) + 2 NO3- (aq) +BaSO4(s)
SO4-2 (aq) + Ba+2 (aq)  BaSO4(s)

19. Molarity Interconverting molarity, moles, volume
M means moles per liter = moles/L
M = moles/L
If you know two things, can determine the third
If you have moles and volume, can determine molarity
3 moles dissolved in 0.5 L = 3moles/0.5L = 6M

20. (Vconc )(Mconc ) = (Vdil )(Mdil )
Molarity - dilution
(Vconc )(Mconc ) = (Vdil )(Mdil )
If you know 3, can solve for the fourth
How many mL of 3M HCl is needed to make 100mL of 1.5 M HCl?
(Vconc)(3M) = (100mL)(1.5M)
Vconc = 50 mL