The integrated rate equation for first order reaction, $A \rightarrow$ product, is

For the elementary reaction, $3 \mathrm{H}_2(g)+\mathrm{N}_2(g) \longrightarrow 2 \mathrm{NH}_3(g)$ identify the correct relation among the following relations:

The activation energy of a reaction is zero. Its rate constant at 280 K is $1.6 \times 10^{-6} \mathrm{~s}^{-1}$, the rate constant at 300 K is

For a chemical reaction rate law is, rate $=k[A]^2[B]$. If $[A]$ is doubled at constant $[B]$, the rate of reaction