Lecture 1 Notes: Intro to Course
[NH4 ] [OH ]
Base ionization constant Kb=
Kb is 1.8 x 10-5 at 25C. This small value tells us that only a small amount of NH3 is present as
NH4+. A strong base reacts essentially completely to give OH- (aq) when put
Lecture 4 Notes: Oxidation Reactions
Guidelines for assigning oxidation numbers
1) In free elements, each atom has an oxidation number of zero. Example H2
2) For ions composed of only one atom the oxidation number is equal to
Lecture 3 Notes: Titrations
Example: Titration of weak acid with strong base
25.0 mL of 0.10 M HCOOH with 0.15 M NaOH (Ka = 1.77 x 10-4 for HCOOH)
1. Volume = 0 mL of NaOH added
Before any NaOH is added, the problem is that of an ionization of a weak acid
Lecture 2 Notes: Acid Buffers
Acid buffer action: The weak acid, HA, transfers protons to OH ions supplied by strong base.
The conjugate base, A-, of the weak acid accepts protons from the H3O+ ions supplied by a strong acid.
A strong acid and the salt
Lecture 5 Notes: Natural Metals
E for flavodoxin is -0.230 V
Is the reduction of vitamin B12 by flavodoxin spontaneous?
E(cell) = E(reduction) - E (oxidation)
= E (vitamin B12) - E (flavodoxin)
= -0.526 V -(-0.230 V) = -0.296 V
G = -nE = -(1)(96485 Cmol-1
Lecture 9 Notes: Gas-Phases
Effect of Temperature on Reaction Rates
A qualitative observation is that reaction rates tend to increase with increased temperature. Now
we will consider the quantitative effect.
In 1889, Svante Arrhenius plotted rat
Lecture 8 Notes: Reaction Mechanism
Investigating Reaction Mechanisms (Ch 13.8)
2NO (g) + O2 (g) 2NO2 (g)
It is experimentally determined that the rate of formation of NO2 is kobs [NO]2[O2]
Overall order = ?
Is a one step mechanism likely?
Lecture 7 Notes: Radioactive Decay
The decay of a nucleus is _ of the number of surrounding nuclei that have decayed.
We can apply first order integrated rate laws:
[A] = [A]0 e-k t
t1/2 = 0.6931
However, instead of concentration,
Lecture 10 Notes: Minimization of Stress
Increasing the temperature can cause reaction to shift in endothermic direction.
= E a,f - E
Lecture 6 Notes: Kinetics
Topics: Rates of Chemical Reactions and Rate Law
When considering a chemical reaction, one must ask whether the reaction will go
(thermodynamics), and how fast the reaction will go (kinetics).