Rate Law/Constant/Orders Flashcards
(29 cards)
What is the definition of reaction rate?
The change in concentration of a reactant or product per unit time.
True or False: The reaction rate is always constant throughout the reaction.
False
What factors can affect the reaction rate?
Concentration, temperature, surface area, and the presence of catalysts.
What is a rate law?
An equation that relates the rate of a reaction to the concentration of its reactants.
Fill in the blank: The rate law is expressed in the form rate = k[A]^m[B]^n, where k is the _______.
rate constant
In the rate law equation, what do the variables m and n represent?
The orders of the reaction with respect to the reactants A and B.
What is the unit of the rate constant k for a first-order reaction?
s^-1
Multiple Choice: Which of the following is NOT a factor that affects reaction rate? A) Temperature B) Catalyst C) Color D) Concentration
C) Color
What does a zero-order reaction imply about the concentration of reactants?
The rate of reaction is independent of the concentration of reactants.
True or False: The rate constant k changes with temperature.
True
What is the general form of a second-order reaction rate law?
rate = k[A]^2 or rate = k[A][B]
Short Answer: How can the rate of a reaction be experimentally determined?
By measuring the change in concentration of reactants or products over time.
Fill in the blank: The rate constant k is specific to a _______ and _______.
reaction; temperature
Multiple Choice: Which order of reaction has a rate that depends on the square of the concentration of a reactant? A) Zero-order B) First-order C) Second-order D) Third-order
C) Second-order
What is the effect of a catalyst on the reaction rate?
A catalyst increases the reaction rate by lowering the activation energy.
True or False: The rate law can be determined from the balanced chemical equation.
False
What is the significance of the order of reaction?
It indicates how the rate is affected by the concentration of reactants.
Fill in the blank: In a first-order reaction, the rate is directly proportional to the _______ of the reactant.
concentration
Short Answer: What is the relationship between temperature and reaction rate?
Generally, as temperature increases, the reaction rate increases.
What type of reaction has a rate that is independent of the concentration of reactants?
Zero-order reaction
True or False: The rate constant k is dimensionless.
False
What is meant by the term ‘activation energy’?
The minimum energy required for a reaction to occur.
Multiple Choice: Which of the following is a characteristic of a first-order reaction? A) Rate doubles when concentration doubles B) Rate is constant regardless of concentration C) Rate depends on the square of the concentration D) None of the above
A) Rate doubles when concentration doubles
What does the slope of a concentration vs. time graph represent for a first-order reaction?
The negative rate constant (-k).
