Number of compounds from the following which cannot undergo Friedel-Crafts reactions is: _________

toluene, nitrobenzene, xylene, cumene, aniline, chlorobenzene, $$m$$-nitroaniline, $$m$$-dinitrobenzene

Total number of electrons present in $$\left(\pi^*\right)$$ molecular orbitals of $$\mathrm{O}_2, \mathrm{O}_2^{+}$$ and $$\mathrm{O}_2^{-}$$ is ________.

A transition metal '$$\mathrm{M}$$' among $$\mathrm{Sc}, \mathrm{Ti}, \mathrm{V}, \mathrm{Cr}, \mathrm{Mn}$$ and $$\mathrm{Fe}$$ has the highest second ionisation enthalpy. The spin-only magnetic moment value of $$\mathrm{M}^{+}$$ ion is _______ BM (Near integer)

(Given atomic number $$\mathrm{Sc}: 21, \mathrm{Ti}: 22, \mathrm{~V}: 23, \mathrm{Cr}: 24, \mathrm{Mn}: 25, \mathrm{Fe}: 26$$)

Consider the following first order gas phase reaction at constant temperature $$ \mathrm{A}(\mathrm{g}) \rightarrow 2 \mathrm{B}(\mathrm{~g})+\mathrm{C}(\mathrm{g})$$

If the total pressure of the gases is found to be 200 torr after 23 $$\mathrm{sec}$$. and 300 torr upon the complete decomposition of A after a very long time, then the rate constant of the given reaction is ________ $$\times 10^{-2} \mathrm{~s}^{-1}$$ (nearest integer)

[Given : $$\log _{10}(2)=0.301$$]