Chem 122 Units Flashcards
[A]^0
Mol/L-Sec
[A]
1/Sec
[A]^2
L/Mol-Sec
k[A]^3
L^2/Mol^2-Sec
k[A]^2[B]
L^2/Mol^2-Sec
k[A][B][C]
L^2/Mol^2-Sec
Rate Must Be:
M/Time
Instantaneous Rates
Tangent Line, Average of tangent line endpoints
Average Rate
Final minus initial and negative slope
Rate factors: (5)
Activation Energy, Temperature (Double every 10 C), Concentration (rate determining step), Surface area, and catalysts.
Effect of Substrate (Reactant) Concentration:
Rate goes up rapidly and plateaus
Effect of Enzyme concentration on rate:
Straight up
Effect of Temperature on reaction rate:
The rate goes up at an angle and then straight down (the heat causes the enzyme to unwrap.)
Effect of pH on the enzyme rate:
An upside down āuā
If the concentration is increased in the rate determining step it will:
increase the rate
Surface area increases concentration by:
Allowing more collisions.
When determining the rate of a chemical reaction:
Activation energy is the most important factor.
Small Ea
More collisions possess enough energy to get over the hump and the reaction occurs faster.
Low Ea means:
Fast, exothermic, lots of products
High Ea means:
Slow, Endothermic, few products
More than two molecule reactions are
rare
Does it fit with the rate law?
- Intermediates cancel out
2. The sum of the elementary steps is the the overall
