The spin-only magnetic moment value of an octahedral complex among \( \mathrm{CoCl_3 \cdot 4NH_3} \), \( \mathrm{NiCl_2 \cdot 6H_2O} \) and \( \mathrm{PtCl_4 \cdot 2HCl} \), which upon reaction with excess of \( \mathrm{AgNO_3} \) gives \( 2 \) moles of \( \mathrm{AgCl} \) is ___________ B.M. (Nearest Integer)
