For the following rate law determine the unit of rate constant. Rate $=-\frac{d[ R ]}{d t}=k[ A ]^{\frac{1}{2}}[ B ]^{2}$
For the following rate law determine the unit of rate constant. Rate $=-\frac{d[ R ]}{d t}=k[ A ]^{\frac{1}{2}}[ B ]^{2}$
The total order of reaction $n=\frac{1}{2}+2=\frac{5}{2}=2.5$ Rate $k[\mathrm{~A}]^{\frac{1}{2}}[\mathrm{~B}]^{2}=[\mathrm{R}]^{\frac{5}{2}}$
$\therefore k=\frac{\text { Rate }}{[\mathrm{R}]^{5 / 2}}$
$\therefore$ unit of $k=\frac{\text { unit of rate }}{\text { (unit of concentration) }^{5 / 2}}$
$=\frac{\left(\mathrm{mol} \mathrm{L}^{-1}\right)^{1} \mathrm{~s}^{-1}}{\left(\mathrm{~mol} \mathrm{~L}^{-1}\right)^{\frac{5}{2}}}$
$=\left(\mathrm{mol} \mathrm{L}^{-1}\right)^{1-\frac{5}{2}} \mathrm{~s}^{-1}$
$=\left(\mathrm{mol} \mathrm{L}^{-1}\right)^{-\frac{3}{2}} \mathrm{~s}^{-1}$
$=(\mathrm{mol})^{\frac{-3}{2}}\left(\mathrm{~L}^{-1}\right)^{\frac{-3}{2}} \mathrm{~s}^{-1}$
$=\mathrm{mol}^{\frac{-3}{2}} \mathrm{~L}^{\frac{+3}{2}} \mathrm{~s}^{-1}$
If the order of reaction $=\frac{5}{2}$ then unit of rate constant $k$ is $\mathrm{L}^{\frac{+3}{2}} \mathrm{~mol}^{\frac{-3}{2}} \mathrm{~s}^{-1}$.
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In hydrogenation reaction at ${27\,^o}C$, it is observed that hydrogen gas pressure falls from $2\,atm$ to $1.2\,atm$ in $50\,\min$. Calculate the rate of disappearance of hydrogen
In hydrogenation reaction at ${27\,^o}C$, it is observed that hydrogen gas pressure falls from $2\,atm$ to $1.2\,atm$ in $50\,\min$. Calculate the rate of disappearance of hydrogen
$A_2 + 2\,B \to 2\,AB$
$[A_2]$
$[B]$
${-d\,[A_2]/dt}$
$0.1$
$0.2$
$1 \times {10^{ - 2}}\,M{s^{ - 1}}$
$0.2$
$0.2$
$2 \times {10^{ - 2}}\,M{s^{ - 1}}$
$0.2$
$0.4$
$8 \times {10^{ - 2}}\,M{s^{ - 1}}$
Order of reaction w.r.t. $A_2$ and $B$ are respectively
$A_2 + 2\,B \to 2\,AB$
| $[A_2]$ | $[B]$ | ${-d\,[A_2]/dt}$ |
| $0.1$ | $0.2$ | $1 \times {10^{ - 2}}\,M{s^{ - 1}}$ |
| $0.2$ | $0.2$ | $2 \times {10^{ - 2}}\,M{s^{ - 1}}$ |
| $0.2$ | $0.4$ | $8 \times {10^{ - 2}}\,M{s^{ - 1}}$ |
Order of reaction w.r.t. $A_2$ and $B$ are respectively
The possible mechanism for the reaction
$2NO + Br \to 2NOBr$ is
$NO + Br_2 \rightleftharpoons NOBr_2$ (Fast)
$NOBr_2 + NO \to 2NOBr$ (Slow)
The rate law expression is
The possible mechanism for the reaction
$2NO + Br \to 2NOBr$ is
$NO + Br_2 \rightleftharpoons NOBr_2$ (Fast)
$NOBr_2 + NO \to 2NOBr$ (Slow)
The rate law expression is
In the reaction : $P + Q \longrightarrow R + S$ the time taken for $75\%$ reaction of $P$ is twice the time taken for $50\%$ reaction of $P$. The concentration of $Q$ varies with reaction time as shown in the figure. The overall order of the reaction is
In the reaction : $P + Q \longrightarrow R + S$ the time taken for $75\%$ reaction of $P$ is twice the time taken for $50\%$ reaction of $P$. The concentration of $Q$ varies with reaction time as shown in the figure. The overall order of the reaction is