Chemical Kinetics Questions

If the half-life ($t_{1/2}$) for a first order reaction is $1$ minute, then the time required for $99.9\%$ completion of the reaction is closest to:

Which one of the following statements for the order of a reaction is INCORRECT?

During the kinetic study of the reaction $2A+B\to C+D$, the following results were obtained:| Run | $[A]$ (M) | $[B]$ (M) | Initial Rate (${\text{mol L}}^{-1}{\text{min}}^{-1}$) ||---|---|---|---|| I | $0.1$ | $0.1$ | $6.0\times 10^{-3}$ || II | $0.3$ | $0.2$ | $7.2\times 10^{-2}$ || III | $0.3$ | $0.4$ | $2.88\times 10^{-1}$ || IV | $0.4$ | $0.1$ | $2.40\times 10^{-2}$ |Based on the above data which one of the following is correct?

The decomposition of phosphine (${\text{PH}}_3$) on tungsten at low pressure is a first-order reaction. It is because the:

The rate of a first-order reaction is $0.04{\text{mol L}}^{-1}{\text{s}}^{-1}$ at $10\text{seconds}$ and $0.03{\text{mol L}}^{-1}{\text{s}}^{-1}$ at $20\text{seconds}$ after initiation of the reaction. The half-life period of the reaction is:

The addition of a catalyst during a chemical reaction alters which of the following quantities?

The rate constant of the reaction $\text{A}⟶\text{B}$ is $0.6\times 10^{-3}\text{mole per second}$. If the concentration of $\text{A}$ is $5\text{M}$, then concentration of $\text{B}$ after $20$ minutes is:

What is the activation energy for a reaction if its rate doubles when the temperature is raised from $20^{\circ }\text{C}$ to $35^{\circ }\text{C}$? ($R=8.314{\text{J mol}}^{-1}{\text{K}}^{-1}$)

In a zero-order reaction for every $10^{\circ }$ rise of temperature, the rate is doubled. If the temperature is increased from $10^{\circ }\text{C}$ to $100^{\circ }\text{C}$, the rate of the reaction will become:

In a reaction, $A+B\to \text{Product}$, rate is doubled when the concentration of $B$ is doubled, and rate increases by a factor of $8$ when the concentrations of both the reactants ($A$ and $B$) are doubled. The rate law for the reaction can be written as:

Activation energy ($E_a$) and rate constants ($k_1$ and $k_2$) of a chemical reaction at two different temperatures ($T_1$ and $T_2$) are related by:

The half life of an enzyme-catalysed reaction is $138\text{s}$. The time required for concentration to fall from $1.28\text{mg/L}$ to $0.04\text{mg/L}$ is:

The rate of $2{\text{N}}_2{\text{O}}_5\to 4{\text{NO}}_2+{\text{O}}_2$ can be written as:$-\frac{d[{\text{N}}_2{\text{O}}_5]}{dt}=k[{\text{N}}_2{\text{O}}_5]$, $\frac{d[{\text{NO}}_2]}{dt}=k^{\prime }[{\text{N}}_2{\text{O}}_5]$, $\frac{d[{\text{O}}_2]}{dt}=k^{\prime \prime }[{\text{N}}_2{\text{O}}_5]$.The relationship between $k,k^{\prime },k^{\prime \prime }$ is:

The unit of rate constant for a zero order reaction is:

For an endothermic reaction, energy of activation is $E_a$ and enthalpy of reaction is $\Delta H$ (both of these in $\text{kJ/mol}$). The minimum value of $E_a$ will be:

For the reaction $N_2{O}_5(g)\to 2N{O}_2(g)+\frac{1}{2}{O}_2(g)$ the value of rate of disappearance of $N_2{O}_5$ is given as $6.25\times 10^{-3}{\text{mol L}}^{-1}{\text{s}}^{-1}$. The rate of formation of $N{O}_2$ and $O_2$ is given respectively as:

For the reaction $A+B\to \text{products}$, it is observed that:(a) doubling the initial concentration of $A$ only, doubles the rate.(b) doubling the initial concentrations of both $A$ and $B$, there is a change by a factor of $8$ in the rate.The rate of this reaction is:

Half life period of a first-order reaction is $1386\text{seconds}$. The specific rate constant of the reaction is:

In the reaction ${\text{BrO}}_3^{-}(aq)+5{\text{Br}}^{-}(aq)+6{\text{H}}^{+}\to 3{\text{Br}}_2(l)+3{\text{H}}_2\text{O}(l)$. The rate of appearance of bromine (${\text{Br}}_2$) is related to rate of disappearance of bromide ions as following:

For the reaction ${\text{N}}_2+3{\text{H}}_2\to 2{\text{NH}}_3$, if $\frac{d[{\text{NH}}_3]}{dt}=2\times 10^{-4}{\text{mol L}}^{-1}{\text{s}}^{-1}$, the value of $-\frac{d[{\text{H}}_2]}{dt}$ would be:

The rate constants $k_1$ and $k_2$ for two different reactions are $10^{16}{e}^{-2000/T}$ and $10^{15}{e}^{-1000/T}$ respectively. The temperature at which $k_1=k_2$ is:

The bromination of acetone that occurs in acid solution is represented by the equation ${\text{CH}}_3{\text{COCH}}_3+{\text{Br}}_2\stackrel{{\text{H}}^{+}}{\to }{\text{CH}}_3{\text{COCH}}_2\text{Br}+{\text{H}}^{+}+{\text{Br}}^{-}$. Based on kinetic data showing the rate is independent of $[{\text{Br}}_2]$, what is the rate equation?

The reaction of hydrogen and iodine monochloride is given as:${\text{H}}_2(g)+2\text{ICl}(g)\to 2\text{HCl}(g)+{\text{I}}_2(g)$ This reaction is of first order with respect to ${\text{H}}_2(g)$ and $\text{ICl}(g)$. The following mechanisms were proposed:Mechanism A: ${\text{H}}_2(g)+2\text{ICl}(g)\to 2\text{HCl}(g)+{\text{I}}_2(g)$ Mechanism B:${\text{H}}_2(g)+\text{ICl}(g)\to \text{HCl}(g)+\text{HI}(g)$ (slow)$\text{HI}(g)+\text{ICl}(g)\to \text{HCl}(g)+{\text{I}}_2(g)$ (fast)Which mechanism is consistent with the rate law?

Consider the reaction${\text{N}}_2(\text{g})+3{\text{H}}_2(\text{g})\to 2{\text{NH}}_3(\text{g})$ The equality relationship between $\frac{d[{\text{NH}}_3]}{dt}$ and $-\frac{d[{\text{H}}_2]}{dt}$ is :

For the reaction$2\text{A}+\text{B}\to 3\text{C}+\text{D}$ Which of the following does not express the reaction rate?

For reaction $aA\to xP$, when $[A]=2.2\text{mM}$, the rate was found to be $2.4{\text{mM s}}^{-1}$. On reducing concentration of $A$ to half, the rate changes to $0.6{\text{mM s}}^{-1}$. The order of reaction with respect to $A$ is:

An endothermic reaction with high activation energy for the forward reaction is given by the diagram: