Lecture 18

Question 1

Compare [A]0 = 0.1M to [A]0 = 1.2 * 10^-8 M. Which one would degrade slower?

Answer 1

[A]0 would degrade slower. A decrease in concentration decreases the reaction rate.

Question 2

What is the mechanisms of a reaction?

Answer 2

A series of elementary steps, leading from reactants to products, where an elementary reaction indicates a molecular collision.

Question 3

What is an intermediate?

Answer 3

a molecule that is generated and consumed over the course of a reaction

Question 4

Are catalysts products or reactants in a reaction?

Answer 4

They are neither products or reactants. They are present at the beginning and end of the mechanism, not used up. They are regenerated over the course of mechanisms.

Question 5

Are higher order collisions simultangeous?

Answer 5

No

Question 6

Is N2 + 2O2 –> 2NO2 an elementary reaction?

Answer 6

No. It is termolecular (1+2 = 3 // look at the coefficients). Termolecular collisions are not probable.

Question 7

Ex: N2 + 2O2 –> 2NO2
Exp rate law = k[N2][O2]
Does the rate law reflect the stoichiometry? What does this indicate?

Answer 7

No. If it did reflect the stoichiometry, [O2] would be squared because it has a coefficient of 2. Not an elementary reaction.

Question 8

What molecular collisions are allowed?

Answer 8

unimolecular and bimolecular