Which of the following graphs represent a first order reaction ($a =$ initial concentration of reactant,$x =$ concentration of reactant consumed,$t =$ time)?

For the gaseous reaction $A(g) \longrightarrow B(g) + C(g) + D(g)$,starting with an initial pressure of $400 \ atm$. If the total pressure after $2 \ hr$ is $800 \ atm$,the value of the rate constant is: (consider the reaction to be $1^{st}$ order): (in $hr^{-1}$)

For a first order reaction $A \to$ product,the rate of reaction at $[A] = 0.2 \, mol \, L^{-1}$ is $1.0 \times 10^{-2} \, mol \, L^{-1} \, min^{-1}$. The half-life period for the reaction is .......... $min$.

The reaction $A + B \xrightarrow{k}$ product is first order with respect to $A$ and zero order with respect to $B$. If $a_0$ and $a_t$ are the concentrations of $A$ at $t = 0$ and after time $t \, sec$ respectively,then select the correct relationship -

$A$ first order reaction takes $23.03 \ minutes$ for $20 \%$ decomposition. Calculate its rate constant.

For the decomposition reaction $2N_2O_5 \rightarrow 4NO_2 + O_2$,the reaction follows first-order kinetics. Which of the following is true?