Embibe Experts Solutions for Chapter: Chemical Kinetics, Exercise 1: Level 1

In a first-order reaction $\mathrm{A}\to \mathrm{B},$ if $\mathrm{k}$ is rate constant and initial concentration of the reactant $\mathrm{A}$ is $0.5 \mathrm{M},$ the half-life is

A drop of a solution (volume$=0.05 \mathrm{ml})$ contains $6\times {10}^{-7} \mathrm{mol}$ of ${\mathrm{H}}^{+}.$ If the rate of disappearance of ${\mathrm{H}}^{+}$ is $6.0\times {10}^5 \mathrm{mol} {\mathrm{lit}}^{-1}{\mathrm{s}}^{-1},$ how long will it take for the ${\mathrm{H}}^{+}$ in the drop to disappear?

The rate expression for the reaction $\mathrm{A}\left(\mathrm{g}\right)+\mathrm{B}\left(\mathrm{g}\right)\to \mathrm{C}\left(\mathrm{g}\right)$ is $\mathrm{k} {\mathrm{C}}_{\mathrm{A}}^{2 } {\mathrm{C}}_{\mathrm{B}}^{1/4}.$ What changes in the initial concentrations of $\mathrm{A}$ and $\mathrm{B}$ will cause the rate of reaction to increase by a factor of eight?

The half life period for catalytic decomposition of ${\mathrm{AB}}_3$ at $50 \mathrm{mM}$ is $4 \mathrm{hrs}$ and at $100 \mathrm{mM}$ it is $2 \mathrm{hrs}.$ The order of reaction is:

The reaction of hydrogen and iodine monochloride is given as:

${\mathrm{H}}_{2 \left(\mathrm{g}\right)}+2{\mathrm{ICl}}_{ \left(\mathrm{g}\right)}⟶2{\mathrm{HCl}}_{ \left(\mathrm{g}\right)}+{\mathrm{I}}_{2 \left(\mathrm{g}\right)}$

The reaction is of a first-order, with respect to ${\mathrm{H}}_{2 \left(\mathrm{g}\right)}$ and ${\mathrm{ICl}}_{ \left(\mathrm{g}\right)},$ following mechanisms were proposed.

Mechanism $\mathrm{A}:$

${\mathrm{H}}_{2 \left(\mathrm{g}\right)}+2\mathrm{ICl}{ }_{\left(\mathrm{g}\right)}⟶2{\mathrm{HCl}}_{ \left(\mathrm{g}\right)}+{\mathrm{I}}_{2 \left(\mathrm{g}\right)}$

Mechanism $\mathrm{B}:$

${\mathrm{H}}_{2 \left(\mathrm{g}\right)}+{\mathrm{ICl}}_{ \left(\mathrm{g}\right)}⟶{\mathrm{HI}}_{ \left(\mathrm{g}\right)};$ slow

$\mathrm{HI}{ }_{\left(\mathrm{g}\right)}+{\mathrm{ICl}}_{ \left(\mathrm{g}\right)}⟶\mathrm{HCl}{ }_{\left(\mathrm{g}\right)}+{\mathrm{I}}_{2 \left(\mathrm{g}\right)};$ fast

Which of the above mechanism(s) can be consistent with the given information about the reaction?

;In the reversible reaction, $2 {\mathrm{NO}}_2\underset{{\mathrm{k}}_2}{\overset{{\mathrm{k}}_1}{\rightleftharpoons }}{\mathrm{N}}_2{\mathrm{O}}_4$ the rate of disappearance of ${\mathrm{NO}}_2$ is equal to:

The hypothetical reaction,

${\mathrm{A}}_2+{\mathrm{B}}_2⟶2\mathrm{AB};$

follows the following mechanism:

${\mathrm{A}}_2\stackrel{\mathrm{Fast}}{\rightleftharpoons }\mathrm{A}+\mathrm{A},$

$\mathrm{A}+{\mathrm{B}}_2\stackrel{\text{ Slow }}{⟶}\mathrm{AB}+\mathrm{B},$

The order of the overall reaction is:

For the reaction system,

$2\mathrm{NO}\left(\mathrm{g}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)⟶2{\mathrm{NO}}_2\left(\mathrm{g}\right)$ volume is suddenly reduced to half its value by increasing the pressure on it. If the reaction is of first order with respect to ${\mathrm{O}}_2$ and second order with respect to $\mathrm{NO},$ the rate of reaction will: