For a first order reaction A ( g ) → 2B ( g ) + C ( g ) at constant...

For a first order reaction

A ( g ) \to 2B ( g ) + C ( g )

at constant volume and 300 K, the total pressure at the beginning

( t = 0 )

and at time are

{P}_{0}and{P}_{0}

, respectively. Initially, only A is present with concentration

{\left[A\right]}_{0}

, and

{t}_{\dfrac{1}{3}}

is the time required for the partial pressure of A to reach

1 / {3}^{rd}

of its initial value. The correct option(s) is (are)
(Assume that all these gases behave as ideal gases) For a first order reaction A ( g ) → 2B ( g ) + C ( g ) at constant volume and 300 K, the total pressure at the

For a first order reaction A ( g ) → 2B ( g ) + C ( g ) at constant volume and 300 K, the total pressure at the

Options

Correct answer

A. What is the initial product in the formation of phenol-formaldehyde polymers?

Step-by-step solution

A \to 2B + C

\begin{cases}t = 0 & {P}_{0} & - - \\ t = t & {P}_{0} - P & 2PP\end{cases}

{P}_{0} + 2P = {P}_{t}

K = \dfrac{1}{t}ln \dfrac{{P}_{0}}{{P}_{0} - P} = \dfrac{1}{t}ln \dfrac{{P}_{0}}{{P}_{0} - \dfrac{\left({P}_{t} - {P}_{0}\right)}{2}}

K = \dfrac{1}{t}ln \dfrac{2{P}_{0}}{3{P}_{0} - {P}_{t}} ⇒ - Kt + \ln 2{P}_{0} = \ln \left(3{P}_{0} - {P}_{t}\right)

And

{t}_{\dfrac{1}{3}} = \dfrac{1}{K}ln \dfrac{{P}_{0}}{\dfrac{{P}_{0}}{3}} = \dfrac{1}{K}\ln 3 =

contant
Rate constant does not depends on concentration

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