Zn + 2H^{+} to Zn^{2+} + H_2The half-life per | vedclass

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

Question

(C) $(I)$ Since $t_{1/2}$ is independent of concentration of $Zn$ at constant $pH$,the order with respect to $[Zn]$ is $1$.$(II)$ Let the rate law be

Vedclass · Accepted Answer

$B, C$ and $D$

Vedclass · Answer

(C) $(I)$ Since $t_{1/2}$ is independent of concentration of $Zn$ at constant $pH$,the order with respect to $[Zn]$ is $1$.$(II)$ Let the rate law be $r = k[Zn]^1[H^{+}]^x$.When $pH = 3$,$[H^{+}] = 10^{-3} \ M$. When $pH = 2$,$[H^{+}] = 10^{-2} \ M$.Given that for constant $[Zn]$,the rate increases by $100$ times when $pH$ changes from $3$ to $2$:$\frac{r_2}{r_1} = \frac{k[Zn][10^{-2}]^x}{k[Zn][10^{-3}]^x} = 100$$10^x = 100 \Rightarrow x = 2$.Thus,the rate law is $\frac{dx}{dt} = k[Zn][H^{+}]^2$. Statement $(B)$ is correct.$(III)$ Checking statement $(C)$: If $[Zn]$ becomes $4[Zn]$ and $[H^{+}]$ becomes $\frac{[H^{+}]}{2}$,then $r' = k[4Zn][\frac{H^{+}}{2}]^2 = k[4Zn][\frac{[H^{+}]^2}{4}] = k[Zn][H^{+}]^2 = r$. Thus,$(C)$ is correct.$(IV)$ Checking statement $(D)$: If $[H^{+}]$ is doubled at constant $[Zn]$,then $r' = k[Zn][2H^{+}]^2 = 4k[Zn][H^{+}]^2 = 4r$. Thus,$(D)$ is correct.Therefore,statements $(B)$,$(C)$,and $(D)$ are correct.

Similar Questions

$A$ reaction is first order in $A$ and second order in $B$.
$(i)$ Write the differential rate equation.
$(ii)$ How is the rate affected on increasing the concentration of $B$ three times?
$(iii)$ How is the rate affected when the concentrations of both $A$ and $B$ are doubled?

If the surface area of the reactants increases,then the order of the reaction:

Which of the following statements is incorrect?

The dimension of the rate constant for a second-order reaction involves:

Vedclass Test Series

Exam Paper Generator

Online Exam Module