Q: Based on the rate law you determined, what is the value of the specific rate constant $k$ (with correct units) for this reaction?

$k = 0.35\ \text{L}^2\text{mol}^{-2}\text{s}^{-1}$

Q: Suppose you start with $[X] = 0.30\ \text{mol L}^{-1}$ and $[Y] = 0.20\ \text{mol L}^{-1}$. What is the initial rate of formation of $Z$?

$2.1 \times 10^{-4}\ \text{mol L}^{-1}\text{s}^{-1}$

Question 1

Given the reaction $2X + Y \rightarrow Z$ and the initial rate data provided, what is the correct rate law for this reaction?

Accepted Answer

$	ext{Rate} = k[X][Y]$

Question 2

Based on the rate law you determined, what is the value of the specific rate constant $k$ (with correct units) for this reaction?

Accepted Answer

$k = 0.35\ 	ext{L}^2	ext{mol}^{-2}	ext{s}^{-1}$

Question 3

If the initial concentration of $[X]$ is doubled while $[Y]$ is kept constant, by what factor does the initial rate of formation of $Z$ change?

Accepted Answer

The rate doubles.

Question 4

If the initial concentration of $[Y]$ is doubled while $[X]$ is kept constant, by what factor does the initial rate of formation of $Z$ change?

Accepted Answer

The rate doubles.

Question 5

Suppose you start with $[X] = 0.30\ 	ext{mol L}^{-1}$ and $[Y] = 0.20\ 	ext{mol L}^{-1}$. What is the initial rate of formation of $Z$?

Accepted Answer

$2.1 	imes 10^{-4}\ 	ext{mol L}^{-1}	ext{s}^{-1}$

Question 6

Which of the following statements best explains why the reaction is first order with respect to $X$?

Accepted Answer

Doubling $[X]$ while keeping $[Y]$ constant doubles the rate.

Question 7

If the reaction were second order with respect to $Y$, what would happen to the rate if $[Y]$ were tripled while $[X]$ remained constant?

Accepted Answer

The rate would increase by a factor of 9.

Question 8

Which of the following is the correct overall order of the reaction based on the rate law you determined?

Accepted Answer

Second order

Question 9

If the units of the rate constant $k$ are $	ext{L}^2	ext{mol}^{-2}	ext{s}^{-1}$, what is the overall order of the reaction?

Accepted Answer

Third order

Question 10

A chemist proposes the following mechanism for the reaction: Step 1 (slow): $X + Y \rightarrow$ intermediate; Step 2 (fast): $X +$ intermediate $\rightarrow Z$. What is the predicted rate law based on this mechanism?

Accepted Answer

$	ext{Rate} = k[X][Y]$

Determining Rate Laws and Rate Constants from Experimental Data

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