REACTIONS: THERMODYNAMIC ASPECTS, KINETICS, AND CATALYSIS - Biomass as a Sustainable Energy Source for the Future - page 155

and chemical equilibrium is treated quite deeply for gas-phase reactions and with
respect to the factors that affect the equilibrium itself. Finally, the main aspects of
catalysis are introduced, in particular the difference between homogeneous and
heterogeneous catalysis and catalyst deactivation.

KEY CONCEPTS

Elementary reactions
Order of reaction
Reaction rate
Activation energy
Arrhenius equation
Chemical equilibrium
Homogeneous catalysis
Heterogeneous catalysis
Catalyst deactivation

SHORT-ANSWER QUESTIONS

5.1 How can you determine whether a reaction is at chemical equilibrium?

5.2 How would you define the reaction rate? Which factors can affect it?

5.3 What is the difference between a global reaction rate expression and one based

on elementary reactions?

5.4 At a certain temperature, why can a certain reaction have multiple values of the

equilibrium constant?

5.5 What is the difference between K c ,K p , and K x ? For a gas-phase reaction, what is

the relation between them?

G 0 5.6 For a reaction taking place at constant p and T, why can we say that the Δ

remains constant, but we cannot say the same for Δ G?

5.7 Why do catalysts not influence the chemical equilibrium?

5.8 Explain the difference between homogeneous and heterogeneous catalysis.

5.9 Does the catalyst concentration affect the reaction rate?

PROBLEMS

By integrating Equation (5.5) with c = c 0 at t = 0 and given that the reaction
proceeds under isothermal conditions, determine the relation between ln c and t.

5.1