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

Which of the following properties is responsible for the development of colour to the colloids?