The rate equation for a reaction $A \rightarrow B$ is $r=k[A]^{0}$. If the initial concentration of the reactant is $a \ mol \ dm^{-3}$,the half-life period of the reaction is

For the reaction $A \rightarrow \text{products}$,the graph of $t_{1/2}$ versus $[A]_0$ is given below. The concentration of $A$ at $10 \ \text{minutes}$ is $.......... \times 10^{-3} \ \text{mol L}^{-1}$ $(nearest \ integer)$. The reaction was started with $2.5 \ \text{mol L}^{-1}$ of $A$.

Which of the following statements is true?

The order of reaction for which the units of rate constant are $mol \ dm^{-3} \ s^{-1}$ is

For a zero-order reaction with rate constant $k$,the slope of the plot of reactant concentration against time is

The decomposition of $NH_3$ on $Pt$ surface is a zero order reaction. If the value of rate constant is $2 \times 10^{-4} \ mol \ L^{-1} \ s^{-1}$,the rates of appearance of $N_2$ and $H_2$ are respectively: