The rate constant of reaction is $1.5 \times 10^7\ \text{s}^{-1}$ at 300 K and $3.0 \times 10^7\ \text{s}^{-1}$ at 330 K. What is the activation energy for the reaction? [ $R \times 2.303 = 19.15\ \text{JK}^{-1}\text{mol}^{-1}$]

The rate constant for the reaction $2\text{N}_2\text{O}_5 \rightarrow 4\text{NO}_2 + \text{O}_2$ is $3.0 \times 10^{-5}\ \text{s}^{-1}$. If the rate is $2.4 \times 10^{-5}\ \text{mole L}^{-1}\ \text{s}^{-1}$ then the concentration of $\text{N}_2\text{O}_5\,(\text{mol L}^{-1})$ is

What is order of radioactive decay of a substance ?

Nano materials not applied in