Chemical Kinetics

Chemical Kinetics

1. Gibb's Free Energy

   • spontaneity of reaction: Positive=not spontaneous Negative=spotaneous
     • + DG => endergonic- consumes energy -DG=> exergonic- gives off energy

2. Collision Theory:

   • rate of reaction is proportional to the number of collisions per second btw the reacting molecules. They must be in the correct orientation and energy.

3. Transition State Theory:

   • when molecules collide with energy higher than the activation energy, they form a transition state in which old bonds are weakened by new bonds forming.

4. Factors affecting reaction rate:

   • *reaction concentrations *Temperature *medium (polar solvents etc.) *catalysts

5. Reaction Orders

   • Zero Order:
     • rate=k[A]^0 [B]^0=k
   • First Order:
     • rate=k[A]^1
   • Second Order:
     • rate=k[A]^1[B]^1 or rate=k[A]^2
   • Mixed Order: reactions that change order over time
     • rate=k1[C][A]^2/k2=k3[A]