Relating plots to the order of a reaction Consider the following reaction: Aprod

Question

Relating plots to the order of a reaction

Consider the following reaction:

Aproducts

The plot of [A] versus t is linear for the zero-order reaction, the plot of ln[A] versus t is linear for the first-order reaction, and the plot of 1[A]versus t is linear for the second-order reaction. [A] represents the concentration of the reactant A.

The linearity of each graph can be used to identify the order of a reaction.

Part A

There are six different reactions you can access in the simulation using the drop-down menu. Which of the following are second-order reactions?

Check all that apply.

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Characteristics of second-order reactions

For a second-order reaction, [A]products, the rate of the reaction is given as rate= k[A]2, where k is the rate constant and [A] is the concentration of reactant A. The integrated rate law for second-order reactions is 1[A]t=kt+1[A]0, where [A]t is the concentration of reactant A at time t, k is the rate constant, and [A]0 is the initial concentration of reactant A. This equation is of the type y=mx+b. Therefore, the plot of 1[A]t versus time is always a straight line with a slope k and a y intercept 1[A]0.

Part B

Consider the second-order reaction:

2HI(g)H2(g)+I2(g)

Use the simulation to find the initial concentration [HI]0 and the rate constant k for the reaction. What will be the concentration of HI after t = 1.90×1010 s ([HI]t) for a reaction starting under the condition in the simulation?

Express your answer in moles per liters to three significant figures.

8.2×103

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In this problem, taking into account the initial concentration of HI, you calculated the concentration of HI at time t = 1.90×1010 s . Similarly, if k and the concentration of HI at a particular time are known, the initial concentration of HI can be calculated.

Examine experimental data

Consider a second-order reaction in which reactant A decomposes according to the chemical equation 2Aproducts.

The data given below is the time, in minutes, and the corresponding change in the concentration of reactant A for this reaction.

Part C

For a second-order reaction, the rate constant k is the slope of the graph of 1[A] versus t. Based on this information and the data given, calculate the rate constant k for the reaction.

Express your answer in M1min1 to three significant figures.

I just need the answer to the last part, I posted the first questions since they are needed to answer this last section. The answer is not 8.1 sec

Explanation / Answer

The only thing that you needed to provide here was the equation you obtained with the data.

According to my calculations, the linear equation for a second order reaction, gives something like this:

y = 1.99942 + 0.03078x

r2 = 0.999990223

so the slope is k = 0.03078 M-1 s-1

All I have to do, is plot 1/A vs t and with that I got these values. Try this answer and tell me in a comment if there's is something wrong or something else you need.

Hope this helps

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