For a first-order reaction $A \to B$,what will be the slope of the graph of $t$ versus $\log(a - x)$?

The rate constant for the oxidation of hydrogen peroxide by $KMnO_4$ is $6.93 \times 10^{-5} \ s^{-1}$. How much time will it take for the volume of a standard $KMnO_4$ solution to decrease from $20 \ mL$ to $8 \ mL$?

If the decomposition reaction $A_{(g)} \to B_{(g)}$ follows first-order kinetics,then the graph of the rate of formation $(R)$ of $B$ against time $t$ will be:

The half-life of a first-order reaction is $20 \text{ min}$. What is the time taken to reduce the initial concentration of the reactant to $\frac{1}{10}$th of its original value (in $\text{ min}$)?

The decomposition of dinitrogen pentoxide $(N_2O_5)$ follows first order rate law. What will be the rate constant from the given data?
At $t = 800 \ s$,$[N_2O_5] = 1.45 \ mol \ L^{-1}$
At $t = 1600 \ s$,$[N_2O_5] = 0.88 \ mol \ L^{-1}$

For a first-order reaction,it takes $40 \ min$ for $90\%$ completion. The half-life of the reaction is ..... (in $min$)