The half time for a second order reaction with equal concentrations of the reactants is $35$ seconds. $99\%$ reaction will be completed in:

For the reaction ${\mathrm{NH}}_4^{+}+{\mathrm{NO}}_2^{-}⟶{\mathrm{N}}_2+2{\mathrm{H}}_2\mathrm{O}$ the following data was recorded

How old is a fossil bone whose ${}^{14}\mathrm{C}$ content is $15.0\%$ of that living bone?

Half life of ${}^{14}\mathrm{C}$ isotope is $5.73\times {10}^3 \mathrm{yr}.$

The following data was recorded for the reaction:
$\mathrm{X}+\mathrm{Y}⟶\mathrm{P}$

The order of the reaction is:

The kinetic data recorded at $278\mathrm{K}$ for the reaction

${\mathrm{NH}}_4^{+}\left(\mathrm{aq}\right)+{\mathrm{NO}}_2^{-}\left(\mathrm{aq}\right)\to {\mathrm{N}}_2\left(\mathrm{g}\right)+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)$ is

The kinetic rate expression and the unit of rate constant (k) of the above reaction are respectively