Problem: An average reaction rate is calculated as the change in the concentration of reactants or products over a period of time in the course of the reaction. An instantaneous reaction rate is the rate at a particular moment in the reaction and is usually determined graphically.The reaction of compound A forming compound B was studied and the following data were collected:Time (s)                    [A] (M)0.                               0.184200.                           0.129500.                           0.069 800.                           0.0311200.                         0.0191500.                         0.016a. What is the average reaction rate between 0 s and 1500 s?b. What is the average reaction rate between 500 s and 1200 s?c. What is the instantaneous rate of the reaction at t = 800 s?

FREE Expert Solution

Average rate of reaction

$\boxed{\mathbf{Rate}\mathbf{=}\frac{\mathbf{\Delta }\mathbf{\left[}\mathbf{A}\mathbf{\right]}}{\mathbf{\Delta t}}}$

a. What is the average reaction rate between 0 s and 1500 s?

***Since A is a reactant, the rate with respect to A is negative (–) since we’re losing reactants.

$\frac{\mathbf{\Delta }\left[\mathbf{A}\right]}{\mathbf{\Delta t}}\mathbf{=}\mathbf{-}\frac{{\left[\mathbf{A}\right]}_{\mathbf{final}}\mathbf{-}{\left[\mathbf{A}\right]}_{\mathbf{initial}}}{{\mathbf{t}}_{\mathbf{final}}\mathbf{-}{\mathbf{t}}_{\mathbf{initial}}}$

$\frac{\mathbf{\Delta }\mathbf{\left[}\mathbf{A}\mathbf{\right]}}{\mathbf{\Delta t}}\mathbf{=}\mathbf{-}\frac{\mathbf{0}\mathbf{.}\mathbf{016}\mathbf{ }\mathbf{M}\mathbf{-}\mathbf{0}\mathbf{.}\mathbf{184}\mathbf{ }\mathbf{M}}{\mathbf{1500}\mathbf{-}\mathbf{0}\mathbf{ }\mathbf{s}}$

$\frac{\mathbf{\Delta }\mathbf{\left[}{\mathbf{O}}_{\mathbf{2}}\mathbf{\right]}}{\mathbf{\Delta t}}$= 1.12×10^‒4 M/s

b. What is the average reaction rate between 500 s and 1200 s?

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