Half life period of a first order reaction is $1386$ seconds. The rate constant of the reaction is

What is the order of the following reaction ?
$2\text{H}_2\text{O}_2 (l) \rightarrow 2\text{H}_2\text{O} (l) + \text{O}_2 (g)$, if rate = $k [\text{H}_2\text{O}_2]$

Which of the following nanomaterial has all the three dimensions $< 100$ nm?

Identify the gas adsorbed by solid to the largest extent at their respective critical temperature.