Exercise-1

In the reaction ${\mathrm{NH}}_4{\mathrm{NO}}_2$ (aq.) $\to {\mathrm{N}}_2( \mathrm{g})+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{D}\right.$the volume of ${\mathrm{N}}_2$ after $20$ min and after a long time is $40\mathrm{ml}$ and $70\mathrm{ml}$ respectively. The value of rate constant is :

If no catalyst $\left({\mathrm{H}}^{+}\right)$ is present in acid hydrolysis of ester then rate constant $\mathrm{k}$ is: (Where ${\mathrm{V}}_0,{ \mathrm{V}}_{\mathrm{t}}$ and ${\mathrm{V}}_{\infty }$ are volumes of $\mathrm{NaOH}$ used to titrate reaction mixture at $\mathrm{t}=0,\mathrm{t}=\mathrm{t}$ and $\mathrm{t}=\infty$)

The following data were obtained in an experiment on inversion of cane sugar; (a first order kinetics)

The rate constant (in ${\mathrm{second}}^{-1}$) is $[\ln 2=0.693]$

Half life of reaction: ${\mathrm{H}}_2{\mathrm{O}}_2\left(\mathrm{aq}\right)⟶{\mathrm{H}}_2\mathrm{O}\left(1\right)+\frac{1}{2}{\mathrm{O}}_2( \mathrm{g})$ is independent of initial concentration of ${\mathrm{H}}_2{\mathrm{O}}_2$ volume of ${\mathrm{O}}_2$ gas after $20$ minute is $5 \mathrm{L}$ at $1$ $\mathrm{atm}$ and $27°\mathrm{C}$ and after completion of reaction $50 \mathrm{L}.$ The rate constant is-

The substance undergoes first-order decomposition. The decomposition follows two parallel first-order reactions:

${\mathrm{K}}_1=1.26\times {10}^{-4}{\sec }^{-1}$ and ${\mathrm{K}}_2=3.8\times {10}^{-5}{\sec }^{-1}$

The percentage distribution of $\mathrm{B}$ and $\mathrm{C}$.

For a hypothetical elementary reaction.

where $\frac{{\mathrm{k}}_1}{{\mathrm{k}}_2}=\frac{1}{2}$

Initially, only $2$ moles of $\mathrm{A}$ are present. The total number of moles of $\mathrm{A}, \mathrm{B}$ and $\mathrm{C}$ at the end of $75\%$ of reaction are:

For the following parallel chain reaction , if the sum of the concentration of $\mathrm{B}$ and $\mathrm{C}$ at any time is $2\mathrm{M}$. What will be $[\mathrm{B}{]}_{\mathrm{t}}$ and ${\left[\mathrm{C}\right]}_{\mathrm{t}}$  respectively?

A radioactive element has a half-life of one day. After three days the amount of the element left will be: