A reaction has a rate constant k = 2.4 times | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(C) The unit of $k$ is $s^{-1}$,which indicates that it is a first-order reaction.For a first-order reaction,the time required for a certain percentag

Vedclass · Accepted Answer

$10$

Vedclass · Answer

(C) The unit of $k$ is $s^{-1}$,which indicates that it is a first-order reaction.For a first-order reaction,the time required for a certain percentage of completion is given by $t = \frac{2.303}{k} \log \frac{[A]_0}{[A]_t}$.For $t_{99.9}$,the remaining concentration is $0.1 \%$ of the initial concentration,so $t_{99.9} = \frac{2.303}{k} \log \frac{100}{0.1} = \frac{2.303}{k} \log 1000 = \frac{2.303 	imes 3}{k}$.For $t_{50}$,the time is the half-life,$t_{50} = \frac{0.693}{k} = \frac{2.303 	imes 0.301}{k}$.The ratio $\frac{t_{99.9}}{t_{50}} = \frac{3 	imes 2.303 / k}{0.301 	imes 2.303 / k} = \frac{3}{0.301} \approx 10$.

$A$ reaction has a rate constant $k = 2.4 \times 10^{-4} \ s^{-1}$. Find the ratio of $t_{99.9}$ to $t_{50}$.

Similar Questions

The rate constant of a first order reaction is $1.15 \times 10^{-3} \ s^{-1}$. How long will $5 \ g$ of reactant take to reduce to $3 \ g$ (in $s$)?

For a first order reaction,a plot of $\log(a-x)$ against time is a straight line with negative slope equal to

For a first-order reaction,the half-life period is $6 \ min$. Find the rate constant of the reaction. (in $min^{-1}$)

In a $1^{st}$ order reaction,$75\%$ of the reactant is consumed in $1.388 \, h$. Find the rate constant of the reaction.

The decomposition of dinitrogen pentoxide $(N_2O_5)$ follows first order rate law. What will be the rate constant from the given data?
At $t = 800 \ s$,$[N_2O_5] = 1.45 \ mol \ L^{-1}$
At $t = 1600 \ s$,$[N_2O_5] = 0.88 \ mol \ L^{-1}$

Vedclass Test Series

Exam Paper Generator

Online Exam Module