Quiz 1 - Chemical Kinetics: Mechanisms | Chemical Kinetics: Mechanisms
General Chemistry 2 - Quiz 1 - Chemical Kinetics: Mechanisms
According to the collision theory, which factor does not increase the rate of a reaction?
Decreasing the surface area of solid reactants would actually reduce the number of effective collisions per unit time, leading to a slower reaction rate. Collision theory states that for a reaction to occur, particles must collide with sufficient energy and proper orientation.
The Arrhenius equation is given by k = Ae−Ea/RT. What does the term Ea represent?
In the Arrhenius equation, Ea represents the activation energy, which is the minimum energy required for a reaction to occur.
In a reaction mechanism, the rate-determining step is identified as the slowest step. How does this step affect the overall rate law of the reaction?
The rate-determining step is the slowest step in a reaction mechanism which limits the speed of the overall reaction. The rate law is influenced by the species involved in this step, and their coefficients in the balanced equation for this step become the order of the reaction with respect to those species.
Which of the following is true about a reaction mechanism?
A reaction mechanism is a detailed sequence of elementary steps that together make up the overall reaction.
For the elementary reaction NO2 + CO → NO + CO2, what is the rate law?
The rate law for an elementary reaction can be directly written from the stoichiometric coefficients of the reactants in the balanced equation as the exponent in the rate law.
Which of the following best describes the role of a catalyst in a chemical reaction?
A catalyst increases the reaction rate by providing an alternative reaction pathway with a lower activation energy, allowing more molecules to react.
For the reaction 2A + B → C, if the rate law is determined to be Rate = k [A]2[B], which of the following can be inferred about the reaction mechanism?
The rate law suggests that the rate-determining step involves two molecules of A and one molecule of B, consistent with a bimolecular reaction in the rate-determining step.
Which of the following statements is true for an elementary reaction?
The rate law for an elementary reaction can be directly written from the stoichiometric coefficients of the reactants in the balanced equation as the exponent in the rate law.
Which of the following best describes the role of an intermediate in a reaction mechanism?
An intermediate is a species that is formed in one step of a reaction mechanism and consumed in a subsequent step, so it does not appear in the overall balanced equation.
Which type of catalysis typically involves the adsorption of reactants onto the surface of a solid catalyst?
In heterogeneous catalysis, the catalyst is in a different phase (usually a solid) than the reactants, and the reaction occurs on the surface of the solid catalyst where the reactants are adsorbed, react, and then desorb as products.