CK-12-Chemistry Intermediate

http://www.ck12.org Chapter 18. Kinetics

TABLE18.2:(continued)

Experiment [S 2 O 82 −] (M) [I−] (M) Initial Rate (M/s)

2 0.080 0.017 1.1× 10 −^4

3 0.16 0.017 2.2× 10 −^4

(b) What is the initial rate of reaction if the concentrations of both S 2 O 82 −and I−are 0.5 M?

9. Nitrogen monoxide reacts with hydrogen at elevated temperatures according to the following equation: 2NO(g)+2H 2 (g)→N 2 (g)+2H 2 O(g).
   Determine the rate law from the following data (Table18.3), and calculate the rate constant for the tempera-
   ture at which these experiments were conducted.

TABLE18.3:Reaction Rate data

Experiment [NO] (M) [H 2 ] (M) Initial Rate (M/s)

1 5.0× 10 −^3 2.0× 10 −^3 1.30× 10 −^5

2 1.0× 10 −^2 2.0× 10 −^3 5.20× 10 −^5

3 1.0× 10 −^2 4.0× 10 −^3 1.04× 10 −^4

Further Reading / Supplemental Links

• ChemicalKinetics:DifferentialRateLaws, http://www.chm.davidson.edu/vce/kinetics/differentialratelaws.ht
  ml


• RateLawsandOrdersofReaction, http://www.saskschools.ca/~bisstchem/modules/module4/lesson3/ratelaw
  equation.htm

Points to Consider

Chemical reactions can generally be broken down into a series of simple steps that convert the reactants into the
products. This set of steps is referred to as the reaction mechanism.

• What is the relationship between a reaction mechanism and the rate law for that reaction?


• What is an intermediate in a chemical reaction?