it is abbreviated as\( PCC\) and is called Collin's reagent. This reagent is used in non aqueous solvent like \(C{H_2}C{l_2}\)
It is a very good reagent because it checks the further oxidation of aldehyde to carboxylic acid while rest oxidising agent oxidise aldehyde into carboxylic acid.
$(A)\,\, HCHO$ $(B) \,\,CH_3COCH_3$
$(C)\,\,PhCOCH_3$ $(D)\,\ PhCOPh$