Answer:
Statements I and II are true.
Explanation:
Let us consider the reaction A → products.
Which of the following statements is or are true?
I. The reaction follows first-order kinetics. TRUE
The expression for a first-order reaction is:
ln[A] = ln[A]₀ - k.t [1]
where,
[A] is the concentration of the reactant A at certain time t
[A]₀ is the initial concentration of A
k is the rate constant
t is the time
If the plot of ln[A] vs. t A is a straight line, it means that the reaction follows a first-order kinetics.
II. The rate constant for the reaction is 3.0×10⁻² s⁻¹. TRUE.
In [1], ln[A]₀ is the intercept and -k the slope of the linear equation. Thus,
-k = −3.0×10⁻² s⁻¹
k = 3.0×10⁻² s⁻¹
III. The initial concentration of [A] was 1.0 M. FALSE.
Since we do not have information about the intercept in the plot of ln[A] vs. t, we do not have enough information to calculate the initial concentration of A.
Statements I and II are true.
