The complex with highest magnitude of crystal field splitting energy $\left(\Delta_{0}\right)$ is :

The major product formed in the Friedel-Craft acylation of chlorobenzene is

The number of $\mathrm{P}-\mathrm{O}-\mathrm{P}$ bonds in $\mathrm{H}_{4} \mathrm{P}_{2} \mathrm{O}_{7},\left(\mathrm{HPO}_{3}\right)_{3}$ and $\mathrm{P}_{4} \mathrm{O}_{10}$ are respectively :

Which of the following statement is correct for paper chromatography?